AAMC MCAT test 5r a

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Practice Test 5R Solutions
®

Solutions

5R

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MCAT

MEDICAL COLLEGE ADMISSION TEST

1


MCAT P RACTICE T EST 5R
S OLUTIONS
Edited, produced, typeset, and illustrated by
Steven A. Leduc
National Director of MCAT Research, Production & Development,
The Princeton Review

Special thanks to:
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Judene Wright

Copyright © 2003, 2001 by Princeton Review, Inc.
All rights reserved.
MCAT is a service mark of the Association of American Medical Colleges (AAMC).

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Version 1.0

www.PrincetonReview.com

MCAT P RACTICE T EST 5R
S OLUTIONS
C ONTENTS :
Physical Sciences ................. 3
Verbal Reasoning .................. 14

Biological Sciences ............ 29

030316

2


PHYSICAL SCIENCES
Passage I
1. B. The value of DH∞ for Reaction 1 is given as –92 kJ. Since DH∞ is negative, the reaction is exothermic, by definition.
2. C. According to the data in Table 1, the equilibrium concentration of NH3(g) (% by volume) increases as the pressure
increases. This eliminates choices A and B, which show the yield decreasing as the pressure increases. To decide between
choices C and D, we first notice that when the pressure increases from 1 atm to 100 atm—which is an increase of 99 atm—
the % NH3(g) by volume at equilibrium jumps significantly, from 15.3 to 80.6. However, when the pressure increases from
100 atm to 200 atm—an increase of 100 atm—the % NH3(g) by volume only increases from 80.6 to 85.8. This indicates
that the % yield increases sharply with pressure initially, but then increases less abruptly at high pressures. This behavior is
illustrated by the graph in choice C.
3. A. The passage states that Reaction 1 is carried out “in the presence of” FeO/Al2K2O4. Furthermore, we notice from
Reaction 1 that neither FeO nor Al2K2O4 is consumed in the reaction. We conclude that this mixture is a catalyst for the

reaction, and the role of a catalyst is to increase the reaction rate.
4. D. Since NH4+ is a cation with a +1 charge, and SO42– is an anion with a –2 charge, we would expect that a combination
of these ions would contain 2 NH4+ ions for each SO42– ion; that is, the compound would be (NH4)2SO4. The balanced
acid–base reaction would be 2 NH3 + H2SO4 Æ (NH4)2SO4.
5. D. Choice A is eliminated since the product of Reaction 1, NH3, is not an ion. Because NH3 has a permanent dipole
moment, we would expect dipole–dipole interactions between NH3 molecules. In addition, NH3 is capable of hydrogen
bonding (the partial positive charge on an H atom of one molecule of NH3 attracted to the partial negative charge on the
N atom of another NH3 molecule).
6. A. Of the ions listed, Mg2+ and H+ are cations, and being electron deficient, are acids (eliminating choices C and D).
Since nitrogen is less electronegative than oxygen and since N3– has a greater negative charge than –OH, N3– is a stronger
base than –OH.

Passage II
7. D. According to the passage, “there is a large electrical repulsion between these two fragments that causes them to . . .
gain kinetic energy.”
8. A. According to Newton’s Third law, the magnitude of the force by Fragment 1 on Fragment 2 is equal to the magnitude
of the force by Fragment 2 on Fragment 1, so choice A must be correct. Since the forces the fragments feel have the same
magnitude, but the fragments have different masses, the accelerations of the fragments must be different; since a = F/m, the
fragment with the greater mass experiences a smaller acceleration, eliminating choice B. Because both fragments start from
rest and have different accelerations, the speeds of the fragments at any moment t will be different (because v = at); this
eliminates choice C. To eliminate choice D, notice that
KE = 12 mv 2 = 12 m (at ) 2 = 12 m

2

( mF t) 2 = 2Fm t 2

Since F is the same for both fragments but m is different, the fragments will have different KE values at each moment t.

3

9. C. First, eliminate choice B. If all of the heavier elements were stable, then there would be naturally-occurring elements
that have more protons in their nucleus than uranium does. As for choices A and D, even if we grant that they are true, they
simply beg the question and do not provide an answer. Why have all of the heavier elements radioactively decayed? Why is
it that heavier elements can be made only in nuclear reactors? According to the passage, the strong nuclear force is a shortrange attractive force that balances the large repulsive force between the positive charges in the nucleus. Once the nucleus
get too large (that is, once the nucleus contains too many protons), we conclude that the short-range strong nuclear force
becomes unable to hold the nucleus together, which is why such large nuclei do not occur naturally (they’ve spontaneous
decayed). The statement in choice C provides a reasonable and direct answer as to why the strong nuclear force becomes
unable to hold large nuclei together.
10. D. According to Coulomb’s law, the force between the two charged fragments, +Q and +Q, is given by the equation
F = kQQ/r2 = kQ2/r2, where r is their separation. Since F is inversely proportional to r2, the graph of F vs. r must decrease
nonlinearly, which is shown in the graph in choice D.
11. A. Neither choice B nor C is applicable here, since there is no mention of electrons in the fusion (or fission) of nuclei.
And according to the passage, the strong nuclear force is an attractive force between the charges in a nucleus, so to fuse two
nuclei together, there is no need to “overcome” an attractive force, eliminating choice D. The answer must be A. Since
both nuclei are positively charged, energy must be provided to force them together and overcome their electrical repulsion.
12. C. Since each fragment (of charge +Q) experiences a decreasing force as it moves away from the other fragment
(because, according to Coulomb’s law, F = kQQ/r2 = kQ2/r2, and r is increasing), each fragment will experience a
decreasing acceleration (a = F/m = kQ2/mr2, where m is the mass of the fragment).

Passage III
13. D. The passage states that CFCs “can undergo photolysis in the upper atomsphere and subsequently assist in the
decomposition of ozone. . . .” Therefore, we can conclude that if a compound were inert in the upper atmosphere, then it
would not “significantly assist” in the depletion of ozone.
14. A. The chlorine atom in Reaction 4 is a radical, Cl•. By definition, a radical is an atom or molecule fragment with one
or more unpaired electrons.
15. B. If we combine Reactions 4 and 5, crossing out the Cl• and ClO• radicals, the net reaction is given in choice B:

Reaction 4: Cl • + O 3 Æ ClO • + O 2

+ Reaction 5: ClO • + O Æ Cl • + O 2
Net reaction: O 3 + O Æ 2 O 2
16. C. First, we find the net reaction of Reactions 1 and 2:
Reaction 1: O 2 Æ O + O

+ Reaction 2: O + O 2 Æ O 3
Net reaction: 2 O 2 Æ O + O 3

Now, to determine whether the overall reaction involves an increase or a decrease in free energy, we calculate DGrxn using
the values for DGf given in Table 1:

4


DGrxn = Â n ◊ DGf, products - Â n ◊ DGf, reactants
= (1 ◊ DGf, O + 1 ◊ DGf, O 3 ) - (2 ◊ DGf, O 2 )
kJ
= (230.1 mol
+ 163.4

kJ
kJ
mol ) - (2 ◊ 0 mol )

>0
Because DGrxn is positive, we can eliminate choices A and B. Choice D is eliminated since it indicates a negative activation
energy (since it shows the activated complex at a lower energy level than the reactants). The answer must be C.
17. D. We calculate DS for the reaction 2 O3 Æ 3 O2 using the values for S given in Table 1:
DSrxn = Â n ◊ Sproducts - Â n ◊ Sreactants

= (3 ◊ SO 2 ) - (2 ◊ SO 3 )
= (3 ◊ 205.0
= 137.4

J
J
mol ◊ K ) - (2 ◊ 238.8 mol ◊ K )

J
mol ◊ K

18. C. In Reactions 3–5, we see that the Cl• generated by the cleavage of a CFC (Reaction 3) causes the decomposition of
O3 (Reaction 4). However, the Cl• is regenerated in Reaction 5, so that only a catalytic amount of CFC is needed to drive
the formation of O2.

Passage IV
19. A. Apply Le Châtelier’s principle to Equation 2. “Excessively moist soil conditions” describe conditions where the
amount of the H2O(l) is increased. Since H2O(l) is a reactant in Equation 2, we would thus expect that an increase in H2O(l)
would shift the equilibrium toward the product side, causing a greater degree of ionization and releasing more OH–(aq).
20. D. Because the statements in choices A, B, and C are all false (since N2 accounts for more than 75% by volume of the
atmosphere, the N2 molecule is nonpolar, and N2 is not a noble gas), the correct response must be D.
21. D. The species that results when an acid loses an H+ is called the conjugate base of that acid. When H2PO4– loses an
H+, it becomes HPO42–. Therefore, HPO42– is the conjugate base of H2PO4–.
22. C. The equilibrium that would best account for an increase in pH would show the formation of OH– ions, so we
eliminate choice A. The reactions in choices B and D are incorrect, since, for example, neither is balanced electrically nor
stoichiometrically, so the best answer here is C.
23. A. Pure liquids are omitted from equilibrium expressions since their concentrations remain essentially constant (not that
they’re zero), so we first eliminate choices B and D. Since Equation 2 shows the formation of OH–, we conclude that
(NH4)2HPO4 is a basic salt, so A is a better response than C.

5


Independent Questions
24. B. First, to balance the given equation, we need only place a coefficient of 2 in front of both the HCl and the NaCl:
Na2CO3 + 2 HCl Æ CO2 + H2O + 2 NaCl
Notice that this affects neither the Na2CO3 nor the CO2. Now, if we treat CO2 as an ideal gas, then 11.2 L of CO2 at STP is
equivalent to 1/2 mole of CO2 (since, by Avogadro’s law, one mole of any ideal gas at STP occupies a volume of 22.4 L).
According to the reaction above, we would need 1/2 mole of Na2CO3 to produce 1/2 mole of CO2. Since a 2 M solution of
Na2CO3 contains 2 moles of Na2CO3 per liter, we would need 1/4 L = 250 mL of this solution to obtain 1/2 mole of Na2CO3.
25. C. The molecule MnO4– is not an exception to the rule that the oxidation number of oxygen is –2. So, if we let x denote
the oxidation number of Mn in MnO4–, then x + 4(–2) = –1, so x = +7. Now, the oxidation number of Mn for the cation
Mn2+ is clearly +2, so the oxidation number of Mn in MnO4– differs from its oxidation number in Mn2+ by (+7) – (+2) = 5.
26. B. First, if the waves strike the shore every 3.0 seconds, then the period of the waves is T = 3.0 seconds. Next, if the
horizontal distance between adjacent crests and troughs is 1.0 m, then the wavelength is twice as much, l = 2.0 m. We now
use the equation v = lf. Since f = 1/T, we have
v=

l 2.0 m
=
= 0.67 m s
T 3.0 s

27. B. The circumference of the circular path is C = 2pr = 2p(4 cm) = 8p cm. Since the particle complete 4 revolutions
(or cycles) per second—that is what “moving on a circular path . . . with a frequency of 4 Hz” means—the particle travels a
total distance of 4 ¥ (8p cm) = 32p cm in one second. Therefore, to travel half this distance, 16p cm, would require half the
time: that is, 1/2 second.

Passage V
28. C. The buffered solution at the beginning of Experiment 1 contains 16 mmol of CDP in 1 L of aqueous solution. Since

10 mL = 1/100 L, we conclude that 10 mL of the solution contains (16/100) mmol of CDP. To find the mass of CDP in 10
mL of this solution, we multiply (16/100) mmol of CDP by its molecular mass:
16
m = ( 100
¥ 10 -3 mol CDP) ¥

403 g
16
ª ( 100
¥ 10 -3 ) ¥ ( 400 g) = (16 ¥ 4) ¥ 10 -3 g = 64 ¥ 10 -3 g = 6.4 ¥ 10 -2 g
mol CDP

29. D. We apply Le Châtelier’s principle. To increase the yield of the product, (CP)n, in Equation 1, we could increase the
concentration of the reactant (which would shift the equilibrium toward the product side). Therefore, we would expect that
increasing the amount of the reactant, CDP, would increase the yield of the product, (CP)n.
30. A. The reactant, CDP, and one of the products, namely HPO42–, both have a stoichiometric coefficient of n in the
balanced reaction (Equation 1 in the passage). Therefore, in the expression for the equilibrium constant for this reaction,
both [CDP] and [HPO42–] must appear with an exponent of n. This eliminates choices B and C. The expression in A is a
better choice than the one in D since the other product of Reaction 1 is (CP)n, not simply CP.
31. C. In Equation 1, which is balanced, the stoichiometric coefficient of the polymer, (CP)n, is 1, and the stoichiometric
coefficient of HPO42– is n. Therefore, the concentration of (CP)n is 1/n times the concentration of HPO42–.
32. C. We use the Henderson–Hasselbalch equation:
pH = pKa + log

[conjugate base]
[weak acid]

Since the solution is buffered at pH 8.7, and pKa = 6.7, we have pH – pKa = 2, so
log

[HPO 4 2 - ]
[HPO 4 2 - ]
= 2 fi
= 10 2 = 100
[H 2 PO 4 ]
[H 2 PO 4 - ]
6


Passage VI
33. A. Because 14C undergoes beta decay, it will not emit an alpha particle or neutron in the decay process; this eliminates
choices B and C. Since the radioactive decay process is 146 C Æ 147 N + -01e - , we see that 14C undergoes b– decay and emits
an electron, -01e - .
34. D. According to the passage, the half-life of 14C is approximately 6000 years. Therefore, a time period of 18,000 years
represents approximately 3 half-lives. If the object currently contains 1000 atoms of 14C, then 1 half-life ago, it contained
2000 atoms of 14C; 2 half-lives ago, it contained 4000 atoms of 14C; and 3 half-lives ago, it contained 8000 atoms of 14C.
35. C. The passage gives the mass of a beta particle as 9 ¥ 10–31 kg. So, if its speed is 3 ¥ 107 m/s, its kinetic energy is
KE = 12 mv 2 =

1
2

(9 ¥ 10 -31 kg)(3 ¥ 10 7 m s) 2

=

1
2

(9)(32 ) ¥ 10 -31 ¥ 1014 J

ª 40 ¥ 10 -17 J
= 4.0 ¥ 10 -16 J
36. A. As stated in the passage, a scintillator is a substance that produces light when it absorbs the energy accompanying
radioactive decay. The scintillator is attached to a photomultiplier that collects this light and converts it into electrical
impulses, which are then counted. These pulses then serve to measure the rate at which decay occurs. If the scintillator
were to be non-transparent to the light it emits, then it would reabsorb some of that light, which the photomultiplier would
then turn into electrical pulses and add to the count (that is, in addition to the pulses that are actually due directly to the
decaying object itself), thereby overestimating the radiation energy and rate of decay. This would clearly produce an
inaccurate reading. To prevent (or at least to minimize) this reabsorption of light, the scintillator should therefore be
(nearly) transparent to the light it emits.
37. A. The energy of a photon of frequency f is given by the equation E = hf, where h is Planck’s constant. Since f = c/l,
we can rewrite the equation for photon energy as E = hc/l. For the photon described in this question, then, we have
E=

hc (6.6 ¥ 10 -34 J ◊ s)(3 ¥ 10 8 m s)
=
l
450 ¥ 10 -9 m
ª

20 ¥ 10 -26 J ◊ m
4.5 ¥ 10 -7 m

ª 4.4 ¥ 10 -19 J

Passage VII
38. C. We first eliminate choices A and B; statement A is false (after all, Cl2 is a gas at room temperature, whereas I2 is not)
and although statement B is true, the relative boiling points of Cl2 and I2 are irrelevant to the determination of the oxidation
state of copper in the compounds it forms in reactions with these substances. To decide between choices C and D, we look

at Table 1, and notice that Cu and Cl2 form CuCl2, while Cu and I2 form CuI. In CuCl2, copper is in a +2 oxidation state,
while in CuI, copper is in only a +1 oxidation state. Since Cu “gives up” two electrons to chlorine but only one to iodine in
these compounds, we would select choice C over choice D. Furthermore, since Cl is higher in the periodic table than I, we
would expect that each Cl atom in Cl2 would have a stronger attraction for electrons than each I atom in I2.
39. C. The nitrate ion, NO3–, has a –1 charge, so a cadmium cation would have a +2 charge in order for the molecule
Cd(NO3)2 to be neutral. Since the chloride ion, Cl–, also has a –1 charge, we expect the combination of Cd and Cl to be
CdCl2 and the balanced reaction between Cd(NO3)2 and NaCl to be Cd(NO3)2 + 2 NaCl Æ CdCl2 + 2 NaNO3.

7


40. B. Looking to the passage for a clue about the product that would most likely form between Cd and S, we notice in
Table 1 that Zn and S form the compound ZnS. Since Cd is in the same family as Zn, it is reasonable to expect that Cd and
S would form the compound CdS. Now sulfur, like oxygen, is most commonly in a –2 oxidation state in its compounds
with other atoms. If the oxidation state of S in CdS is –2, then the oxidation state of Cd must be +2.
41. A. First, eliminate choice B (where is the source of carbon to form CO2?). Since evolution of gas occurs only with the
addition of HNO3, HNO3 must react with copper metal. Copper metal (Cu0) must be oxidized during this reaction, and
HNO3 must be reduced. Of the remaining choices (A, C, and D), the only logical choice for the product of the reduction of
HNO3 is NO.
42. B. Because boiling-point elevation is a colligative property, the solution whose solute dissociates into the greater
number of ions will be the one with the higher boiling point. Since Zn(NO3)2 dissociates into 3 ions (Zn2+ + 2 NO3–) while
AgNO3 dissociates into only 2 ions (Ag+ + NO3–), we’d expect the boiling point of Zn(NO3)2(aq) to be higher than that of
AgNO3(aq).
43. D. The AgNO3(aq) solution contains Ag+ ions; as Cu atoms are oxidized, Ag+ ions are reduced to Ag, which is the “new
metal [that] forms on the surface of the Cu strip.” Also, note that we can eliminate choices A, B, and C, since it is highly
unlikely that the cation Ag+ would be oxidized—or that Ag or Cu would be reduced—in this situation.

Passage VIII
44. C. The temperature, T, is 673 K in Trial 5. According to the data for Trial 5 given in Table 1, the current I is 2 A, and
the voltage across the wire is 28 V. Therefore, the power dissipated by the wire is P = IV = (2 A)(28 V) = 56 W.

[Alternatively, since the resistance R is approximately 14 W, the power dissipated is P = I 2R = (2 A)2(14 W) = 56 W.]
45. D. In the first paragraph of the passage, the mass of the wire is given to be m = 4 ¥ 10–3 kg. Since the volume of the
wire is given in the question to be V = 5 ¥ 10–7 m3, the density of the wire is

r=

m 4 ¥ 10 -3 kg
=
= 0.8 ¥ 10 4 kg m 3 = 8 ¥ 10 3 kg m 3 = 8, 000 kg m 3
V 5 ¥ 10 -7 m 3

46. A. According to the data in Table 1, R increases as T increases (as we can see by reading the values of R as the
temperature increases from Trial 1 through Trial 5). This eliminates the graphs in B and D, which show the resistance R
either constant or decreasing with temperature. Since the only choices left are the graphs in choices A and C, the question
becomes, “Does R increase linearly with T?” Comparing Trials 2 and 3, then 3 and 4, then 4 and 5, we see that R increases
by a steady 2.6 W for every 100 K increase in temperature. Therefore, R does increase linearly with T, and the answer is A.
47. D. From the expression given in the last paragraph of the passage, AsT4, we see that the energy radiated from the
heated wire each second is proportional to T 4. So, if T increases by a factor of 2 , the energy radiated each second
increases by a factor of ( 2 ) 4 = [( 2 )2 ]2 = [2]2 = 4 .
48. A. We use the equation q = mcDT, where m is the mass of the sample being heated and c is the specific heat of the
sample (in this case, it is the iron wire). Since the mass of the wire is m = 4 ¥ 10–3 kg, the specific heat of iron is c = 460
J/kg·K, and DT = 573 K – 373 K = 200 K, we have
q = mcDT = ( 4 ¥ 10 -3 kg)( 460

J
)(200
kg ◊ K

K) = 368 J

[Note: The question uses the term “heat capacity” where it should use the term “specific heat.”]

8


49. D. According to the data in Table 1 for Trial 1, the resistance of the wire was R1 = 4 W when T = 293 K. When T = 673
K (Trial 5), the resistance rose to R5 = 13.9 W ª 14 W. Therefore, if the voltage remained constant at 28 V, the current
decreased, from
I1 =

V 28 V
=
=7A
R1
4W

to

I5 =

V
28 V
=
=2A
R5 14 W

Independent Questions
50. B. Because the activity decreased to 60/240 = 1/4 its initial value, this means that 2 half-lives elapsed, since (1/2)2 is
equal to 1/4. If a time period of 2 half-lives is equal to 24 minutes, then one half-life must be 12 minutes.
51. C. Since the molecules in the gas phase of a substance are much more disordered than in the solid phase, the phase

change from solid to gas (sublimation) represents an increase in the entropy, S. That is, DS > 0.
52. C. The Doppler Effect implies that when the source of a sound moves away from the observer, the perceived frequency
is lower than the emitted frequency.
53. A. As the diagram below shows, water at –0.1∞C and 1.0 torr is vapor, and as the pressure is increased at constant
temperature, the vapor will become a solid and then a liquid:

off the diagram
at P = 200 atm
liquid

pressure (torr)

solid

vapor
4.6
1.0
–3.0

0.01
–0.1
temperature (∞C)

54. B. Because opposite charges attract, the negatively-charged particle will move toward the fixed positive charge Q; this
eliminates choices A and C.
–q

+Q

r

The negatively-charged particle experiences a force (F = kQq/r2) as it approaches +Q, so it will undergo an acceleration
(a = F/m = kQq/mr2, where m is the mass of the –q particle). Since the –q charge is accelerating, its speed of approach
cannot be constant. This eliminates choice D.

9


Passage IX
55. D. As stated in the first paragraph of the passage, the sample XT-n contains n% Ti, where n = 0, 1, 3, or 5. Looking at
the data in Table 1, we notice that the solubility of XT-n increases as n increases, so choices A and B are eliminated. Since
the entry in each row is greater for toluene than for THF, we conclude that the XTs are more soluble in toluene than in THF.
56. D. Even if there were any indication in the passage that the XTs are even capable of hydrogen bonding, the formation
of hydrogen bonds would not decrease the weight of a sample, so we eliminate choice A. Next, according to the data in
Table 2, the masses (and therefore the weights) of the samples decrease by 20% when heated from 20∞C to 700∞C; the loss
of some electrons, even if they escaped from the heating chamber, could not account for this much of a decrease in mass,
so we eliminate choice B. As for choice C, the removal of protons from nuclei requires extreme conditions (like those in a
nuclear reactor); it is highly unlikely that simply heating the compound to 700∞C would cause a nuclear reaction. Choice D
provides the most reasonable explanation for the loss of mass by the samples as they are heated.
57. B. The transition metal titanium (Ti, atomic number 22) is in the 3d “block” of the Periodic Table, which means its
valence electrons are in 3d orbitals. Titanium doesn’t contain electrons in 4p or 5f orbitals, so choices C and D are
eliminated, and titanium’s 2s electrons (choice A) are not in the valence shell, so they’re unavailable to form bonds.
58. C. Of the elements listed in the choices, only zirconium (Zr, atomic number 40) is in the same family (group) as
titanium (Ti, atomic number 22). The elements in each family of the Periodic Table have similar properties and have
identical (or very similar) outer configurations.
59. B. Since oxygen is an element in Period 2, it has only s and p orbitals and can form no more than four hybrid orbitals,
so choice C is eliminated immediately. Choice D should be eliminated immediately as well (s2p2 hybridization?). The
oxygen atom in THF is bonded to two carbon atoms, so there must be four equivalent hybrid orbitals on the oxygen atom,
formed by sp3 hybridization; two contain lone pairs and two contain a single electron each, which will form the s bonds
with the carbons.

60. A. Since THF can participate in hydrogen bonding with H2O, but toluene cannot, we’d expect THF to be more soluble
than toluene in H2O. Choice B is false (since there are no hydrogen bonds between toluene and water to compare with
those between THF and water), and while the statements in choices C and D are true, they don’t answer the question.

Passage X
61. C. When the toboggan begins its slide from Point A, it has gravitational potential energy (relative to Point B), which is
converted to kinetic energy as the toboggan slides down the hill. Since the passage states that the toboggan experiences
friction as it slides, some of the potential energy is also converted to heat (thermal energy). Therefore, the energy
conversion is best described by choice C: potential to kinetic and thermal.
62. B. According to the passage, the toboggan is opposed by a constant 60 N frictional force when it’s sliding down the hill.
Since the toboggan feels this force for the entire length, l, along the hill, the work done by sliding friction on the toboggan
is equal to –(60 N)(l), so the energy lost to friction is (60 N)(l).
63. A. We apply Conservation of Total Momentum to this completely inelastic collision. Since the toboggan and rider
(T&R) are stationary before the collision, their momentum before the collision is zero, so the total momentum before the
collision is simply MS&RvS&R, the momentum of the sled and rider (S&R). The momentum after the collision is (MS&R +
MT&R)v¢. Therefore,
MS& R vS& R = ( MS& R + MT& R )v ¢ fi v ¢ =

MS& R vS& R
(3 kg + 47 kg) ◊ (10 m s)
50
=
=
m s ª 4.55 m s
MS& R + MT& R (3 kg + 47 kg) + (6 kg + 54 kg) 11

10


64. A. The passage states that, to the right of Point B, the sled and rider are opposed by a 50 N frictional force, so Ffrict = 50

N. Since Ffrict = mN, and N = MS&Rg = (3 kg + 47 kg)(10 m/s2) = 500 N, we have

m=

Ffrict
50 N
1
=
=
= 0.1
500 N 10
N

65. B. The snowball will land when it has fallen a vertical distance of y = 20 m. Let’s first figure out how long this will
take. Using Big Five # 3 (with v0y = 0, since the ball is thrown horizontally), we find that
y = 12 gt 2 fi 20 m = 12 (10

m 2
)t
s2

fi t = 2 s

Because the snowball’s horizontal speed is vx = 25 m/s, the snowball would, in this time, travel a horizontal distance of
x = vxt = (25 m/s)(2 s) = 50 m
Since this equals the horizontal distance from Point A to Point B, the snowball will land at Point B.
Point A
snowball

y = 20 m

t = 2 sec

Point B

x = 50 m

66. D. We use Conservation of Mechanical Energy. The passage states that the sled and rider slide free of friction from
Point A to Point B, so the gravitational potential energy of the sled and rider at Point A is transformed into kinetic energy at
Point B. Therefore,
PE Æ KE fi Mgh = 12 Mv 2

fi v = 2gh

fi v µ h

If the sled and rider start at a point on the hill that is 10 m lower than Point A, then the sled and rider’s initial height above
Point B is being reduced from 20 m to 10 m, a decrease by a factor of 2. Since v is proportional to h , if h is reduced by
a factor of 2, then v will be reduced by factor of 2 .

Passage XI
67. D. As the diagram below shows, the distance between adjacent nodes (labeled N) on a standing wave is always equal to
half the wavelength, l/2:
l

N

N

N
1

2

l

11

N

N


68. A. The traveling waves whose superposition generates a standing wave travel in opposite directions, eliminating
choices B and C. The oppositely-directed traveling waves must have equal amplitudes (choice A) since the resultant
standing wave has displacement zero at the node positions (where the equal-amplitude traveling waves arrive exactly out of
phase with each other and thus completely cancel).
69. B. That the light emitted by the laser is coherent is stated in the first sentence of the passage, so Item II is true, and we
can eliminate choices A and C. If the laser has only one mode of oscillation, then it produces only one wavelength of light
(since, according to the passage, “laser cavities have mode numbers that are related to the allowed cavity wavelength[s].”
Because the laser produces light of only one wavelength, the light is monochromatic (“one color”), so Item I is true, and the
answer must be B. (Note that we didn’t need to check Item III, but, if we did, since laser light is sharp and focused, it
would not be characterized as diffuse.)
70. B. If we substitute lm = c/fm into the equation mlm = 2L (both of which are given in the passage), we find that
m◊

14
c
2 Lfm 2( 13 m)(9 ¥ 10 Hz)
= 2 L fi m =
=
= 2 ¥ 10 6

fm
c
3 ¥ 10 8 m s

71. D. Because l = c/f, we have lbeat = c/fbeat. Therefore, since fbeat = fm+1 – fm, we have
l beat =

c
c
=
fbeat
fm +1 - fm

Independent Questions
72. C. By Archimedes’ Principle, the buoyant force exerted by the unknown liquid on the object is given by Bunknown =
runknownVg, and the buoyant force exerted by benzene is given by Bbenzene = rbenzeneVg. Thus, the ratio Bunknown/Bbenzene is
Bunknown r unknown Vg r unknown
=
=
Bbenzene
r benzene Vg
r benzene
Since we’re given that Bunknown = 12 N and Bbenzene = 5 N, the ratio Bunknown/Bbenzene is equal to 12/5. Therefore,

r unknown 12
=
5
r benzene

fi r unknown =

12
12 7
84
168
=
= 1.68r H 2 O ª 1.7r H 2 O
r benzene = Ê r H 2 O ˆ =
r
r
¯ 50 H 2 O 100 H 2 O
5
5 Ë 10

This tells us that the specific gravity of the unknown liquid is approximately 1.7.
73. B. We apply Conservation of Total Momentum to this perfectly inelastic collision. Since the block is stationary before
the collision, its momentum before the collision is zero, so the total momentum before the collision is simply mobjvobj, the
momentum of the sliding object. The momentum after the collision is (mobj + mblock)v¢. Therefore,
mobj vobj = ( mobj + mblock )v ¢ fi v ¢ =

mobj
mobj + mblock

vobj =

1 kg
vobj = 14 vobj = 14 (8 m s) = 2 m s
1 kg + 3 kg

74. B. The equilibrium is Ca(OH)2(s)

Ca2+(aq) + 2 OH–(aq). Increasing the acidity of the solution has the effect of
reducing the concentration of OH–(aq). By Le Châtelier’s principle, removing a product causes a shift toward the products;
therefore, additional Ca(OH)2(s) will dissolve. Since the value of Ksp can be changed only by a change in temperature, the
answer must be B.

12


75. A. For nearsighted individuals, light from distant objects is focused in front of the retina, which occurs if the focal
length of the lens of the eye is smaller than the distance to the retina. A divergent corrective lens is required to cause the
light from distant objects to diverge slightly before entering the lens of the eye, so that it may be focused on the retina.
diverging
corrective lens
retina

retina

nearsighted eye

nearsightedness
corrected

76. A. The principal quantum number, n, has nothing to with the number of valence electrons of an atom (choice C) or with
the mass number (choice D). And choice B is eliminated since, for example, the 3s, 3p, and 3d orbitals all have different
shapes but the same principal quantum number (namely, n = 3), so the principal quantum number cannot be a “measure” of
the approximate shape of an electron cloud. The best response here must be A (and the higher the value of n, the larger the
radial size of the electron cloud).
77. B. The weight of the unknown solid is given by the equation wsolid = rsolidVg, and, by Archimedes’ Principle, the
buoyant force exerted by the water on the solid is given by B = rH OVg. Thus, the ratio wsolid/B is
2

wsolid rsolid Vg rsolid
=
=
B
r H 2 O Vg r H 2 O
Because the solid weighs 31.6 N but has an apparent weight of only 19.8 N when submerged in water, the buoyant force on
the object must be 31.6 – 19.8 = 11.8 N. Since wsolid = 31.6 N and B = 11.8 N, the ratio wsolid/B is also equal to 31.6/11.8.
Therefore,

rsolid 31.6
=
ª 2.68
r H 2 O 11.8
This tells us that the specific gravity of the solid is approximately 2.68.

13


VERBAL REASONING
Passage I
78. D
A: A main theme of the passage is that competition between state and local governments can be destructive. No positive
benefits are mentioned. Furthermore, competition between private firms is never discussed; subnational governments
compete with each other to attract private firms to their area.
B: As in choice A, this statement contradicts a main idea of the passage—that competition can have negative effects. A
secondary problem with this choice is that efficiency is never mentioned in the passage.
C: The passage makes only two references to the national level. First, the author indicates that national economic
development is not characterized by competition (lines 4-6). Second, the author cites the critics’ claim that local and
state competition does not contribute to national productivity (lines 39-43). Neither reference supports a link between

subnational competition and incentives for national development policy.
D: Yes. The author cites the critics’ claim that cooperation would be more likely than competition to result in
increased national (“overall”) productivity (lines 39-44). The passage also describes a case in which increased
cooperation between jurisdictions in the Monongahela River Valley may better address those jurisdictions’
economic problems than would competition (lines 72-83).
79. B
A: The primary purpose of the author is to discuss competition and cooperation on a subnational level. No role for national
officials is mentioned.
B: Yes. The author describes one successful attempt at cooperation, an effort organized by local leaders (lines 8083).
C: Academic researchers are never discussed in the passage.
D: The author does not discuss any role for media representatives.
80. C
A: According to the passage, local leaders in the Monongahela region worked to increase cooperation and decrease
competition between jurisdictions (lines 70-83). If these efforts were followed by prosperity, the lesson would be to
cooperate more, not less (and so compete less, not more). For both choices A and B, remember that the main idea of the
passage is that cooperation may be more advantageous than competition at subnational levels.
B: According to the final paragraph, local jurisdictions had competed in the past, but now are managing to cooperate in the
face of a regional economic downturn (lines 70-83). If this cooperation were followed by prosperity, less competition
would be called for.
C: Yes. If local leaders’ cooperative efforts (lines 80-83) were followed by prosperity, it is likely that continued
cooperation would lead to continued prosperity for the region.
D: The author does not say that local governments in the Valley region ever received federal grants, nor does the passage
draw any link between federal moneys and either prosperity or cooperation.
81. C
Note: To be the credited response, the answer choice must both present an assumption that can reasonably be attributed to
the author and be inconsistent with the new information given in the question.
A: This choice is too extreme; the author does not make this assumption. The author indicates that cooperation is difficult
(lines 44-55), not that it is impossible. In fact, the passage presents a specific example of cooperation between local
jurisdictions (lines 77-83).
B: This choice is out of scope (“state law”) and too extreme (“only if”); the author does not make this assumption. State

law is never mentioned, only pacts, policies, and agreements within and between states and localities. Furthermore, an
example of cooperation is given with no suggestion that state law played any role (lines 70-83).
C: Yes. In the final paragraph, the author states that “Economic conditions may ultimately serve as the catalyst for
greater cooperation….” (lines 70-71). This statement is followed by the one example of a successful attempt at
cooperation given in the passage; this cooperation occurred when the region was experiencing economic
difficulties (lines 73-80). Thus, the author does make the assumption that cooperation is most likely in times of
economic stress. The study cited in the question gives cases in which cooperation followed a period of economic
improvement, and so choice C does describe an assumption that is called into question by the study.
14


D: This is not an assumption made by the author. In fact, the final paragraph presents a case in which local leaders crossed
state lines to foster cooperation between jurisdictions (lines 80-83).
82. D
Item I:

The passage indicates that a difference between national and state or local economic activity is that state and
local economic development is competitive and that state and local governments are “awash in competition”
(lines 4-9). Thus we can infer that national governments do not exhibit competitive economic behavior.
Item II: Yes. This is directly stated in lines 4-9.
Item III: Yes. This is directly stated in lines 4-9.
83. A
A: Yes. In lines 44-46, the passage mentions the failure of Great Lakes states’ governors to keep communities within
those states from pirating or stealing economic developments from each other. This example is introduced with
the more general statement that cooperation is elusive (line 44).
B: The experience of the Great Lakes states is one of a failed attempt to restrict competition. Furthermore, the author does
not indicate that many other state governments have made similar attempts, and so the word “usually” is too extreme.
C: The passage makes no such comparison between state and local governments. The fact that some state governments
failed (lines 44-45) does not in and of itself indicate that local governments are or would have been more successful.
Finally, while local leaders organized the successful Monongahela attempt at cooperation (lines 80-83), the author does

not indicate that this can be extrapolated into a generalized comparison between the effectiveness of state and local
leaders.
D: This choice is both out of scope and too extreme. The power of national governments to regulate competition is never
discussed. Furthermore, the Monongahela case is an example of local leaders successfully regulating or limiting local
competition (lines 72-83).

Passage II
84. B
A: The author explains in lines 59-64 that false memories cannot always be distinguished from correct or true memories.
B: Yes. This is the main idea of the passage. In paragraphs 2, 3 and 4 the author explains how schemas, once
instantiated, help us to understand new information and act upon it. In the final paragraph, the passage
discusses how there may be glitches or flaws in that process that also could affect our memory and
comprehension of events.
C: While the author does state that certain things may be forgotten (lines 60-64), the passage does not indicate that this
would necessarily be true for important things. For that reason, this choice is too extreme. Furthermore, while
imperfect recall is one aspect of schema theory, it is not presented as the most important aspect of it, or as the reason
why schema theory is itself important. Compare this choice to answer choice B.
D: Schemas are activated and instantiated when we are confronted with situations similar to those we have experienced in
the past (lines 8-15). Thus memory is activated in these cases by familiar, not unfamiliar situations.
85. D
A: This choice is inconsistent with the main idea of the passage, which is in part that schemas and scripts (a special type of
schema) are activated in situations that are similar to events and experiences from our past. In cases where scripts are
active, then, encounters with certain events are not new learning experiences, but are affected by our past experiences.
B: In lines 60-64, the passage states that we may remember information that was never part of the original event.
C: As in choices A and B, this statement contradicts the passage. The very nature of a script is that once developed, it can
be used to help us understand and take action in new instances (paragraphs 3 and 4). Compare this choice with choice
D. Choice C is the opposite of the credited response.
D: Yes. Scripts are a special form of schema (lines 22-24), and scripts not only help us understand new instances of
familiar situations, but also guide our behavior in those contexts (lines 22-24). The author presents the
restaurant scenario as an example of how this occurs.

15


86. A
Item I:

Item II:
Item III:

Yes. Slot filling occurs when a script created by previous experiences helps us to understand and fill in
gaps in other, similar experiences (lines 35-52). In this choice, the child has already had one year of school,
presumably with significant similarities to the second year.
A child first learning to ride a bicycle would not necessarily have had other similar experiences in the past.
As for Item II, a child first learning the alphabet would not necessarily have had previous experience with
similar situations that could have created a schema or that would lead to slot filling within that schema.

87. D
A: The passage only discusses inferences, correct or incorrect, that are made within schemas (lines 35-52, 60-64).
B: The author does not discuss partial activation of scripts nor suggest in any way that partial activation cannot occur.
This choice may sound familiar, as the author does discuss instantiation of a script based on partial information (lines
15-19). Always be sure to go back to the passage and reread carefully.
C: While it is likely that scripts are instantiated subconsciously (without our direct knowledge), the author never states it.
Most importantly, the author does not make a connection between the way in which schemas are instantiated (lines 1221, 35-46) and recall error as described in the question and in the passage (lines 60-64).
D: Yes. The author states that inferencing may lead to recall errors and that some information may be forgotten
(lines 56-64). If different readers recalled the same text differently, this would provide evidence that recall
errors do in fact occur.
88. B
A: The passage does not suggest that scripts are instantiated through a deliberate or conscious act. Notice the wording of
the passage. For example, in lines 14-15, the author states that a “schema is thus instantiated by the new information,”

not that the person instantiates it through a deliberate act of will.
B: Yes. The author explains that scripts, when activated, affect both how we process new information and how we
behave based on that information (lines 10-12, 22-24). Schemas and scripts are based on memory or prior
knowledge (lines 3-4, for example).
C: While scripts provide general information about particular circumstances (lines 32-34), slot filling provides specific,
not generalized information within that script (lines 35-52). Notice the word “however” in line 35. It is at that point that
the author shifts from discussing scripts in general to describing the particular function of slot filling.
D: Activation of the script influences processing of new information (lines 10-12). Inferencing occurs after activation and
instantiation, when slot filling occurs (lines 35-52). Thus inferencing depends on the availability of specific pieces of
information from the past, not on processing the new information itself.
89. D
A: Instantiation depends on the availability of an appropriate old, pre-existing schema, not a new schema.
B: Alteration of a schema may occur when slot filling and inferencing occurs (lines 56-64). This happens during or after
instantiation (lines 35-46). It does not determine whether or not instantiation has occurred.
C: As described by the author, instantiation depends on the quality of the information [whether or not it matches a preexisting schema (lines 12-15)], not its quantity.
D: Yes. In lines 12-15, the author explains that instantiation occurs when new information is judged to be “similar
enough to the content of the schema.”
90. C
A: Careful reading is never suggested as a factor in recall errors, certainly not as a cause of error.
B: According to the passage, errors occur when slots are inappropriately filled in a current situation with information from
the schema (lines 59-64), not when the schema (prior knowledge) is incomplete.
C: Yes. A person may fill in slots in a current situation [inferencing (lines 39, 49)] with information from the
schema. While the situations are similar (as they must be for the schema to be activated and instantiated), they
may not match exactly, and those slots may be filled with information that does not match the current reality.
The person may then later remember these things as if they actually happened in that more recent situation
(lines 35-45, 53-64).
D: Instantiation of multiple schemas is never discussed in the passage.

16

91. A
A: Yes. An understanding of schema theory would most likely lead the teacher to teach reading in a way that
created and/or utilized pre-existing knowledge structures. The development of background knowledge would
help create such structures.
B: Nothing in the passage suggests that improved pronunciation would either utilize or develop “organized knowledge
structures in memory” (lines 3-4).
C: While memory is involved in this choice, rote memorization would be unlikely to provide the kind of generic
knowledge structures that could be applied to new situations (lines 3-7). Compare this choice to answer choice A.
D: The credited response must involve the development or use of schemas or “organized knowledge structures in memory”
(lines 3-4). Nothing in the passage indicates that an explanation of an unfamiliar word would help create a schema.
Given that the word is unfamiliar, it is also unlikely that the explanation would draw on or utilize a schema.
92. B
Item I:

Item II:

Item III:

Inferences occur when a person fills in empty spaces in the current text with details from an instantiated script.
A script is not instantiated unless it is significantly similar to, and so most likely appropriate for, the current text
or situation (lines 12-15). The passage does not discuss the activation of inappropriate or wrong texts.
Yes. Inferencing occurs when empty slots in a text are filled in with details from a pre-existing schema
(lines 35-45). When information came only from the schema and did not in fact exist in the text being read,
a person may still later incorrectly remember them as part of that text (lines 59-64), essentially
“rewriting” the text in their memory.
Inferences are made when the reader takes information from a pre-existing schema and inserts it into gaps in a
text (lines 35-45). Skimming a text to acquire specific facts does not involve this use of pre-existing memory
structures, but only the current text itself.

93. B
A: The passage does not indicate that the formation or use of knowledge structures requires effort or purpose, as in
concentrated study.
B: Yes. The author indicates that schemas are formed through previous experiences (lines 3-7), and that schemas
provide a context that helps us to comprehend and utilize new information (lines 10-12, 22-24).
C: Schemas help us to comprehend new situations when not all of the facts are present, as shown by the example of
recognition of a face when only a few details are available (lines 15-21).
D: As in choice A, the passage does not indicate that activation and instantiation of schemas requires any conscious act of
will.

Passage III
94. B
A: The author uses quantum mechanics as an example of a new [“in our own time” (lines 40-43)] scientific research
tradition that has not managed to overcome most people’s common-sense view of “the world as being populated by
substantial objects, with fixed and precise properties” (lines 40-45).
B: Yes. The main idea of the third paragraph is that some world views persist despite the appearance of scientific
traditions that contradict those views. The author offers quantum physics as an example of a scientific theory
that has not managed to shake most people’s common-sense view of “the world as being populated by substantial
objects, with fixed and precise properties” (lines 40-45).
C: This is the right answer to the wrong question. It is people’s belief in indetermination (lines 62-68), not quantum
mechanics, that is incompatible with the idea that we live in a universe governed by natural laws (lines 68-72).
D: See answer choice A. According to the passage, most people refuse to change their world view to accommodate the
insights of quantum mechanics (lines 40-45).

17


95. C
A: This choice takes words out of the context of the passage. Our social, political, and moral beliefs contradict the idea
that all physical changes are subject to the same unchanging natural laws (lines 62-72).

B: This choice also takes words and ideas from the passage out of context. Our social, political, and moral beliefs are
themselves a broader system of cultural attitudes. Such systems sometimes conflict with scientific theories and
traditions (lines 32-40, 62-72).
C: Yes. According to the passage, the scientific tradition that holds that all physical changes are subject to natural
law has been accepted since the 17th century (lines 55-59). However, most of our social, political, and moral
beliefs are inconsistent with the idea that these laws could apply to human beings and perhaps higher animals
(lines 68-72).
D: While the author does argue that Darwinism and Marxism have been accepted by “reflective people” (lines 26-31), the
author draws no direct connection between those research traditions and the social, political, and moral beliefs
discussed in lines 64-72.
96. B
A: Newton’s ideas were “eventually” (lines 21-22) accepted after a “process of readjustment” (line 26). Thus the words
“readily” and “quickly” are too extreme.
B: Yes. This choice corresponds to the author’s description of the process of readjustment that led to acceptance of
Newton’s ideas (lines 14-26).
C: The passage indicates that most people eventually modified their world view to bring it into line with Newton’s ideas
(lines 14-26). There is no indication that the implications of Newton’s theories were ignored, or that most people’s
acceptance of those theories was feigned or only superficial.
D: The Newtonian view of reality was eventually accepted, not rejected (lines 21-26).
97. D
A: The author refers to this claim in order to make the argument that some long-standing scientific traditions (in this case,
since the 17th century) have still not been accepted by most people (lines 49-68), and that the strength of old world
views may not necessarily fade over time. This choice is not consistent with the main ideas of the last two paragraphs.
B: The author writes that natural laws may be either statistical or nonstatistical (lines 58-59). The passage gives no
indication that the laws governing human actions must be statistical in nature, nor does the application of physical laws
to humans indicate that some physical changes can only be explained by statistical laws.
C: The passage states that in the 17th century, physical laws, not theories, were thought to apply to all physical objects or
changes (lines 55-59). Secondly, it is the author, not (as far as we know) people in the 17th century who assume that
these laws apply equally to human beings (lines 62-64).
D: Yes. The view that all physical changes are completely determined would, according to the author, apply to

human beings as well (lines 62-64).
98. A
Item I:
Item II:

Item III:

Yes. The new information in the question describes people changing their views of reality in order to
accommodate new scientific findings.
See the explanation for Item I. The question gives an example of adaptability and acceptance of changing world
views. This choice indicates that some new scientific ideas may never find acceptance in the face of
contradictory world views.
See the explanations for Items I and II. This choice describes resistance to, not acceptance of new scientific ideas
(lines 62-72).

99. C
A: Remember the main idea of the passage. The author argues that behaviorism is not widely accepted due to the strength
of the old world view in which inner mental states exist (lines 32-37, 45-47). The passage never indicates that the
theory of behaviorism is itself weak.
B: This is the right answer to the wrong question. The author’s discussion of the application of natural law to human
behavior comes later in the passage, in a different context (lines 55-68).
C: Yes. According to the author, the fact that people still believe in inner mental states indicates that the scientific
tradition of behaviorism has not been able to supplant or transform an old world view that contradicts this
scientific theory (lines 32-40).
18


D: While behaviorism may be a relatively new (very new is too extreme) tradition, the author does not discuss it or the
contradictory belief in inner states in order to make that claim. Always keep the main idea of the paragraph in mind
when answering “support” or “in order to” questions.

Passage IV
100. D
A: The passage never suggests that CO2 is poisonous to fish. According to the CO2 theory, it could have been a decrease in
the dissolved CO2 level in the ocean waters (and an increase in atmospheric CO2) that lead to extinctions of marine life
by inhibiting the growth of algae, the base of the food chain (lines 56-62).
B: Dust is never mentioned in the context of the CO2 theory. This choice illegitimately combines aspects of the two
different theories presented in the passage (lines 8-11 for the first, 56-62 for the second).
C: This choice contradicts the passage. Fish may in fact eat algae, or other creatures that themselves eat algae (lines 6062). However, the increase in atmospheric CO2 would cause a decrease in CO2 in ocean waters (due to increases in
temperatures) (lines 54-59). Decreases in dissolved CO2 would cause algae to decline, not to flourish (lines 59-60).
D: Yes. An increase in atmospheric CO2 would cause global warming (lines 46-51). Higher temperatures would
cause less CO2 to dissolve in ocean waters (lines 56-59). As dissolved CO2 levels fell, so would the population of
algae, which sit at the base of the oceanic food chain (lines 59-61). Disruption of the food chain could then have
led to the extinction of a variety of marine species (lines 60-62), including species of fish.
101. A
Note: Notice the word “would” in the question. The credited response must be something that these measurements would,
not just could show, prove or indicate.
A: Yes. The CO2 theory posits that increases in atmospheric CO2 would have caused decreases in levels of CO2
dissolved in ocean waters (lines 56-59). Ice cores would indicate if such a change did in fact occur.
B: The new information in the question describes the possibility of measurement, not what those measurements would
show. Compare this choice to answer choice A. This choice is too extreme.
C: The new information in the question states only that measurements could be made, not what those measurements would
be. Even if it were shown that CO2 levels had fallen in the oceans at the K–T boundary, that would not be sufficient to
prove that the cause was an asteroid strike. This choice is also too extreme.
D: See the explanation for choice C. Even if decreased levels of oceanic CO2 levels were found (and we don’t know that
they would be), that would be insufficient evidence to either disprove the dust scenario or prove the CO2 theory.
102. D
Note: Notice that the passage discusses only asteroid strikes on dry land (lines 8-11, 22) or in shallow ocean beds (line 22).
Avoid a trap by going back to the passage and re-reading carefully.
A: Such warming would occur if a 10 km asteroid hit in a bed of carbonate rock (lines 48-51), not in the deepest part of

the ocean.
B: A large enough asteroid could cause mass extinctions if it hit a layer of carbonate rock [on dry land or in ocean
shallows (lines 20-27)]. There is no indication in the passage that a hit in deep ocean would release CO2 into the
atmosphere and set off a chain of events leading to large-scale extinctions.
C: Nowhere in the passage are extinctions limited to aquatic species discussed. Neither does the author present evidence
suggesting that an asteroid hit in deep water would cause any extinction of marine species.
D: Yes. The author only discusses asteroid impacts which might send up clouds of smoke and dust (lines 8-11) (and
so presumably occur on dry land), or which release CO2 into the atmosphere by colliding with beds of carbonate
rock on dry land or in shallow water (lines 20-23, 45-46, 49-50).

19


103. A
A: Yes. The CO2 hypothesis is based on the claim that a major asteroid impact on a bed of carbonate rock would
release CO2 into the air, causing global warming and a decrease in oceanic CO2 levels. If a major asteroid hit on
carbonate rock were not followed by climatic change, it would significantly undermine the causal claims at the
heart of the CO2 theory.
B: In the first paragraph, the author explains that high iridium levels at the K–T boundary inspired the idea that an asteroid
struck the Earth at that time. The iridium evidence is consistent with both theories presented in the passage, and would
support, not challenge the CO2 theory.
C: The CO2 theory argues that increased levels of atmospheric CO2 would lead to global warming (lines 28-32, 44-53).
Further correlation between CO2 levels and global warming would strengthen, not weaken the CO2 theory.
D: The CO2 theory does not rest on the claim that only asteroid impact could lead to increases in global CO2. In fact, in the
context of presenting the CO2 theory, the author describes other factors that increase atmospheric CO2 levels, such as
burning of fossil fuels (lines 32-38).
104. C
A: The possibility of a loss of carbonate rock is not addressed by the passage. Even if we were to speculate that an asteroid
hit that released CO2 from carbonate rocks would entail a reduction in the rocks’ mass (and this speculation would not
be sufficiently supported by the passage), there is no connection to be made to an ash-spewing volcano.

B: The passage indicates just the opposite. Dust and smoke filling the atmosphere would block sunlight from reaching the
Earth (lines 10-11). It is reasonable to assume that massive amounts of ash would have a similar blocking effect.
C: Yes. The author states that the dust and smoke from an asteroid impact could have temporarily cooled the Earth
by blocking out sunlight (lines 8-17). It is reasonable to assume that massive amounts of ash in the atmosphere
would have a similar effect.
D: This is the right answer to the wrong question. The passage makes no connection between dust, smoke, or ash in the
atmosphere (the first theory presented, in the first paragraph) and increases in CO2 (the second theory described, in the
rest of the passage).
105. D
A: This choice is too extreme. According to the passage, if the CO2 theory is valid, then high levels of CO2 may have lead
to large-scale extinctions, including that of the dinosaurs, by causing global warming. However, the author does not
suggest that all forms of life were or would have been destroyed. Finally, the wording of this answer choice (“survive
in high levels of CO2”) appears to indicate that it is the CO2 itself that kills, not its indirect effects through global
warming.
B: According to the passage, large amounts of dust and smoke in the atmosphere would lead to a rapid decrease in
temperature and a temporary “winter” (lines 8-11). Beware of opposite answer choices.
C: The passage makes no such comparison. The only reference in the passage to a species that is directly sensitive to CO2
levels is to a marine species, algae (lines 57-60).
D: Yes. The author describes two theories in the passage, both of which explain the extinctions as the result of the
impact of a large asteroid or comet. The author appears to prefer the CO2 theory as shown by the problems
raised regarding the first theory (lines 13-17) and by the last line of the passage, “Thus, global warming could
have led to the extinction of the dinosaurs.”
106. A
A: Yes. The author states that low-level global warming of 2–4 ∞C due to burning of fossil fuels may lead to melting
of the polar ice caps and flooding (lines 38-43). We can infer that this flooding would be caused by an increase in
sea level due to the melting ice. Sea levels would have risen much more dramatically at the K–T boundary if the
temperature had increased 5–20 ∞C, lasting for 10,000 years (lines 46-53). Thus, if the main theory presented in
the passage, the CO2 theory, is correct, we would find increased sea levels at the K–T boundary.
B: Excess iridium is mentioned in the context of the “dust and smoke” theory (lines 5-11), a theory which according to the
author has serious weaknesses (lines 13-17). However, the presence of excess iridium would also be consistent with the

CO2 theory, which also claims that the primary cause of extinction was an asteroid strike (lines 18-20). Thus, if the
main hypothesis presented in the passage (the CO2 theory) is correct, excess iridium could well be present.
C: The main theory presented in the passage, the CO2 theory, argues that major extinctions did occur at the K–T boundary
(lines 60-66).

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D: As in choices B and C, this choice contradicts the passage. The CO2 theory is predicated on the claim that atmospheric
CO2 levels rose (lines 23-27), not that they (and the composition of the atmosphere) remained constant.
107. B
A: The author believes that asteroids may have indirectly, not directly, caused the dinosaurs’ extinction. Global warming
would have affected the entire planet; there would have been no need for the dinosaurs to be located near the impact
site.
B: Yes. In both of the scenarios described, a consequence of the asteroid or comet impact would be slowing of plant
growth (lines 11-13, 60-65). In the context of discussing the CO2 theory (the author’s preferred explanation), the
author explains that reduction in plant growth disrupts the food chain, and so indicates that starvation was
likely a major cause of extinction.
C: The author may well believe that dust filled the air after an impact, just that the dust itself was not sufficient to cause
mass extinction (lines 13-20)
D: The passage states just the opposite. Decreased levels of CO2 in the oceans could have lead to a decrease in the algae
population, and so disruption of the entire marine food chain (lines 56-62).

Passage V
Note: This passage is particularly confusing because the author’s own position on the issue of whether or not Picasso was in
fact a “cerebral structurer” as a young child, and whether or not he did in fact “begin again” as an adult artist is never made
clear (see lines 8-12, 35-41). Note as well that the questions never ask for the author’s own views on those points. Don’t
get distracted by things that are left unclear in the passage if they are not necessary for answering the questions.
108. D
A: The author argues that Picasso was not a genius or “frankly precocious” as a child (lines 41-45), nor was his work

effortless (lines 22-26, 32-35). His achievements arose from the transformation or metamorphosis that came later (lines
43-45, 52-54).
B: While we know from the passage that Picasso and Braque invented cubism (line 10), the passage does not indicate that
Picasso rejected the art movements of his time (he could have built upon them, for example), or that such rejection
would itself be a cause of his artistic accomplishments. Be careful not to use outside knowledge.
C: Only one example of revision is given (lines 61-64). We do not know from the passage that Picasso had a practice of
making many revisions, or that revision was a reason for his level of artistic achievement.
D: Yes. The primary purpose of the passage is to assess Picasso’s work along two related lines. First, what is the
relationship between his mature work and his artistic creation as a child. Second, what is the relationship
between his work as a child and as an adult, and a childlike or “unreflective” and spontaneous approach to art.
According to Apollinaire and to the author, Picasso’s “spectacular progress” came when he transformed himself
into an “unreflective virtuoso, who relies on nature” (lines 46-54). Picasso’s later apparent spontaneity is
contrasted with his academic, literal, and precise work as a child around the age of nine (lines 24-29).
109. C
A: This choice is too literal. The passage never suggests that Picasso [an example of an artist who relies on nature (lines
50-52)] painted naturalistic scenes. In fact, the “fragmented and distorted” works from his childhood, the “harbingers
[forerunners] of his later genius” (lines 3-7) indicate that he did not paint naturalistic scenes or objects. His unrealistic
portrait of Gertrude Stein provides additional evidence along these lines (lines 59-64).
B: It is unlikely that the “unreflective virtuoso who relies on nature” would consciously refer to or employ defined
aesthetic principles, even elementary ones. This is more likely true of an academic painter or “cerebral structurer.”
C: Yes. The author centers the passage on a basic contrast between childhood or childlike art on one hand, and
academic, literal, and precise art on the other. The “cerebral structurer” represents the latter, while the
“unreflective virtuoso” represents the former category. An adult artist who draws like a child works not from
rules and tradition, but with intuitive spontaneity and adventurousness (lines 22-29, 59-64).
D: This choice is too extreme. According to the passage, the “unreflective virtuoso” Picasso still displayed mastery of his
art. Compare this choice to answer choice C.
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110. D

A: This choice is partially correct, and so entirely wrong. Picasso’s early drawings are described as unusually skilled and
his progress as spectacular (lines 41-45). However, the author rejects the standard story of Picasso’s precocious
childhood talent (lines 13-15, 41-45).
B: The author explicitly criticizes the standard story of Picasso’s precocious talent (lines 13-15, 41-45). Thus the author is
not neutral.
C: This directly contradicts the author’s rejection of the standard claim that Picasso displayed a precocious genius from
early childhood (lines 13-15, 41-45).
D: Yes. See the explanations above (and lines 13-15 for the standard story, lines 41-45 for the author’s opinion).
111. A
A: Yes. Picasso himself claimed that his first drawings were academic, literal, and precise, and that he later
transformed himself into an entirely different kind of painter (lines 22-29). He also argued that he had to
entirely begin again as an adult painter (lines 15-21). This is contradicted by the author’s assertion that Picasso’s
early works contained aspects of distortion, tricks, puns, playfulness, etc. that would appear in his adult
creations. This indicates that Picasso was not a purely academic and realistic painter in his youth, and that there
is some continuity between his youthful creations and his mature artistic style.
B: Picasso’s later work was characterized by distortion (lines 61-64). Thus this choice is consistent, not inconsistent with
the claim that we can see the seeds of Picasso’s adult style in his work as a child.
C: The assertion made in the question is not directly relevant to the lack of drawings from Picasso’s first eight years.
Therefore, it is not inconsistent.
D: See the explanation for choice B. The author claims that Picasso transformed himself into an “unreflective virtuoso”
(lines 47-54) who learned to “draw like a child” as an adult (lines 27-29). Thus the playfulness of his youthful graphic
experimentation (lines 8-12) is entirely consistent with the claim that these experiments were precursors of his mature
artistic style.
112. C
A: Picasso indicates his goals through his statement that “it has taken me a whole lifetime to learn to draw like a child”
(lines 27-29). Nothing in the passage indicates that piecing a work together out of found objects is a childlike approach
to art.
B: There is nothing particularly childlike about muted or subtle colors and elongated figures.
C: Yes. Simple figures and bright colors represent a childlike style.
D: Rendering “hard-edged” multifaceted perspectives would require a level of skill and purposefulness beyond the

capacity of an imprecise and childlike painter.
113. B
Note: The statement made in the question is new information. It is inconsistent with the claims made in the passage by
Picasso and Apollinaire. Both claim that Picasso became an “unreflective virtuoso” later in life.
A: This choice is inconsistent with the new claim made in the question. Raphael drew in an academic, precise, and realistic
manner (lines 24-29), that is, as a “cerebral structurer.”
B: Yes. Exuberant experimentation would more likely characterize an “unreflective virtuoso who relies on nature”
than a “cerebral structurer who relies on understanding.” Picasso and Apollinaire claim that Picasso became an
artist of the first type later in life, but “childlike” early drawings would indicate that he was such an artist from
the beginning.
C: As in choice A, this statement is consistent with Picasso and Apollinaire’s analyses, not with the new claim made in the
question.
D: Revision of Stein’s portrait from memory has no direct relevance to the argument about the nature of Picasso’s art in his
childhood. This choice is out of the scope of the question.
114. C
A: We must take the retort in the context of the passage and the main idea of the paragraph in which it appears. This choice
is too literal. The author uses Stein’s portrait to illustrate Apollinaire’s claim that Picasso left behind realism as he
metamorphosed into an artist of the first type (lines 50-64). This choice inappropriately indicates that the portrait was
intended to be realistic at some time in the future.
B: See the explanation for choice A. The portrait was not intended to be realistic or accurate. Secondly, the author
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indicates that the portrait was finished at the time Picasso made his remark (line 63).
C: Yes. The main idea of this (and the previous) paragraph is that Picasso left behind realism and became a more
intuitive, spontaneous, and adventurous (i.e., childlike) painter in this stage of his life. Thus the example of the
portrait is intended to illustrate how Picasso was now guided by concerns other than accuracy of a likeness or
realism in his work.
D: The author never suggests that Picasso intended to teach viewers of his paintings how to see art in a different way.
Furthermore, the main idea of this part of the passage is that Picasso had left behind the academic or analytic approach

to art for a more “unreflective” and childlike style.
115. A
A: Yes. A cerebral structurer “relies on understanding” (line 48), and understanding would be necessary to both
create and appreciate a novel written with many layers of meaning.
B: Emotion is never directly discussed in the passage. There is nothing in the passage to suggest even indirectly that a
novel written with academic precision [qualities which characterized Picasso in his cerebral phase (lines 24-26, 50-51)]
would have great emotional power.
C: While Picasso in his cerebral phase did paint in a realistic manner (lines 24-26), this choice does not match up with the
contrast presented in the passage between the “unreflective virtuoso who relies on nature” and the “cerebral structurer
who relies on understanding.” There is nothing uniquely cerebral, academic, or intellectual about terse (succinct) and
realistic dialogue.
D: Symbolism is never suggested by the passage as an aspect of a cerebral style.
116. B
Note: The credited response must both accurately represent the author’s views in the passage and be relevant to the new
information in the question.
A: This choice contradicts the author’s argument that Picasso made striking progress after his early years, and that his first
drawings as a child were not “frankly precocious” (lines 41-45).
B: Yes. The author claims that Picasso’s childhood drawings were very skilled, but not “frankly precocious” (lines
41-45). Thus the new information in the question is consistent with the author’s views that the nine-year-old
Picasso was not yet a uniquely skilled artist.
C: If Picasso’s early work was in fact childlike [i.e., similar to the work of other children, in contradiction to Picasso’s
own claims (lines 21-26)], this would indicate that the transition away from a cerebral structurer into a more “childlike”
artist came earlier than the age of nine. This choice is inconsistent with the new information presented in the question.
Furthermore, it is unclear from the passage exactly what the author’s position is on this topic. The author indicates that
Picasso may in fact not have made a radical transformation from Apollinaire’s second kind of artist to the first kind
(lines 8-12, 35-41). And yet the author cites Picasso and Apollinaire’s opinions that such a radical metamorphosis did
occur without directly refuting them (lines 15-29, 46-67), and at times in apparent agreement.
D: The new information in the question contradicts Picasso’s claim that his first drawings were not childlike (lines 21-26).
117. B
A: This choice strengthens Picasso’s claim. In fact, the argument in this choice is made by Picasso himself (lines 15-17).

B: Yes. If the naïveté which characterized children’s art does not in fact disappear, but is available on some level to
the adult artist, it would weaken Picasso’s claim that the adult artist must “begin...from the beginning.” (Notice
that the author himself makes the assertion given in the answer choice in lines 11-12.)
C: Formal artistic training is not a relevant issue in the passage. The fact that some artists, trained or untrained, produce
only childlike works provides no proof that those artists carried over that quality from their own childhood and did not
“begin again” as adults.
D: This choice would tend to strengthen Picasso’s claim that childlike qualities do not automatically carry over from
childhood into adulthood. (It doesn’t quite qualify as a “strengthen” answer choice, however, as we do not know for
sure that these artists are adults, or that if they are adults that they painted in a naïve, nonacademic style as children.)

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Passage VI
118. A
A: Yes. The author introduces the passage by stating that the classification of Neandertals (as direct or distant
relatives to modern humans) is “One of the hottest topics in anthropology today” (lines 1-3) and “the subject of a
long and contentious debate” (lines 6-8). The rest of the passage either directly or indirectly addresses this issue.
B: The author states that we do not know whether they are the direct ancestors of modern human beings (lines 1-12). This
choice contradicts the main idea of the passage, which is that the classification of Neandertals has not yet been
determined.
C: Notice the word “primary” in the question. While the use of stone tools is a significant fact about Neandertals, it does
not represent the primary significance of Neandertals.
D: See the explanation for choice C. Burial of the dead is one clue to Neandertals’ potential humanness (lines 26-28), but it
is not presented as the reason why Neandertals are so fascinating to anthropologists.
119. D
A: While advances in the technology of stone tools occurred, the passage does not suggest that those advances were driven
by a need for more sophisticated technology. The invention and refinement of the Levallois technique, for example, is
not described as a response to changing conditions that necessitated more refined tools.
B: While the passage describes one instance of slowing of the rate of change after a technological innovation (lines 6066), the author does not indicate that this is representative of rates of technological change in general. The word

“normally” makes this choice incorrect.
C: Radiocarbon dating is never mentioned in the passage. Be careful not to rely on outside knowledge.
D: Yes. The author states that “Stone tools clearly signal the pace of change in human prehistory” (lines 55-56),
indicating that the tools made and used by a species tell us something about that species. The passage as a whole
describes aspects and characteristics of the Neandertal as a way of exploring their true nature.
120. A
A: Yes. Use process of elimination! We know from the passage that Homo erectus predated the existence of modern
humans (lines 3-5). The new information in the question tells us that they existed long before the appearance of
the Neandertal, making it more likely (although not certain) that Homo erectus was an ancestor (direct or
distant) to both Homo sapiens sapiens and the Neandertal. This choice is the best supported of the four options.
B: The new information about Homo erectus tells us nothing new about the direct relationship between apes, the
Neandertal, and modern humans. This choice is a more extreme version of choice A, and so is less likely.
C: Even if Neandertal is not a direct ancestor of modern humans, the passage indicates that they would still be related,
even if distantly (lines 10-12). The new information in the question about Homo erectus provides no clue that a
completely separate human family tree exists.
D: As in choice B, this statement is a much more extreme version of A, and so is even less supported by the passage.
121. B
A: Tools remained few and crude until the development of the Levallois technique. The Neandertals refined that technique
even further (lines 56-66). Thus this choice does not accurately describe the tools used by the Neandertals.
B: Yes. The author claims that the Neandertals made a wide range of artifacts without providing specific examples
of different kinds of tools. Thus, support for that claim is weak.
C: The author never claims that the Neandertals were highly intelligent. The passage states that if cranial capacity were the
only measure, they would have impressive mental powers (lines 21-25), but never claims that quantity is in fact the
only measure. Furthermore, even if the passage did claim that the Neandertals were highly intelligent, that in and of
itself would not provide strong support for claims about their resourceful tool-making.
D: The Neandertals refined the Levallois technique; they did not invent it (lines 60-64).

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122. D
A: The author discusses the large cranial capacity of the Neandertal, but not as a criterion for humanness (lines 20-25). In
fact, it would make them different from modern humans, who have a smaller brain.
B: The Neandertals did use tools, and we can speculate that they used tools to make tools with the Levallois technique
(tools would be needed to strike flakes of stone from a rock). However, tool use is not given in the passage as a primary
criterion for humanness.
C: The author never discusses weaponry. The correct answer must be supported by the passage.
D: Yes. The author describes burial ritual as a “uniquely human activity” (lines 27-28). Thus a toy that recited
religious verses (performed rituals) would, among the four choices, be most human on that criterion.

Passage VII
123. D
A: This statement is made in the passage (lines 1-2), but it is too narrow to be the main idea.
B: Thomas and Beulah is in fact divided into two, almost-equal parts (lines 2-3), but this statement is too narrow to be the
main idea of the entire passage.
C: This is one theme of the passage (lines 6-8). However, it does not include the other major theme; the poems also
describe the “single most important events and the resulting mind-sets in the separate lives of Thomas and Beulah”
(lines 4-8). Notice the words “not only” and “but also” in the cited sentences, which indicate that there are two main
themes in the passage. The correct answer must include both.
D: Yes. The “psychological and emotional lives of two individuals” would include both their separate and shared
experiences.
124. C
A: Events connected to beautiful objects (a silk handkerchief, the Eiffel Tower, a flower, a music box) are linked to Beulah
(lines 15-20, 44-47), while pain and guilt are associated with Thomas (lines 20-27, 41-43).
B: Beulah desires a sensuous life (lines 44-47), while events linked to ships and water characterize Thomas’s existence
(lines 41-43).
C: Yes. The author introduces the passage with the statement that the collection of poems “presents not only the
single most important events and the resultant mind-sets” in each separate life, but also “the significant events of
their shared lives” (lines 4-8). The events described in the passage are both ordinary [parents quarreling,
sweeping the floor (lines 47-53)] and extraordinary [the death of a friend (lines 9-12)].

D: This choice is too extreme. Events linked to water and ships are connected in the passage to a gap in Thomas’s life
between desire and fulfillment (lines 31-41). However, the link as described is limited to these poems and these
characters. The author does not suggest that this association always exists.
125. D
A: This choice is only partially correct. Beulah’s preference for a pianola does represent her mixed feeling about the
marriage (lines 56-66). However, the “one pierced cry” refers to Thomas’s own individual association between music
and guilt (lines 20-27). Notice where each reference appears in the passage. Only the last paragraph discusses the pair’s
mixed feelings about their marriage.
B: Thomas’s “always jiving” represents his own individual life and experiences (lines 27-30). The passage never mentions
Beulah’s desire “to hear wine pouring.”
C: This is the right answer to the wrong question. These quotes illustrate Thomas’s (lines 36-37) and Beulah’s (lines 5053) individual lives and thoughts, not their mixed feelings about their marriage.
D: Yes. Both quotes come from the final paragraph (lines 63-64, 66-69). The purpose of that paragraph is to present
the two characters’ perspectives on their marriage, and to portray their mixed feelings. Thomas experiences
longing as he wraps the yellow scarf around Beulah’s shoulders, and yet he wonders, “How did I get here?”
Beulah turns her back on her father reluctantly, as she walks towards her new life with Thomas.

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