Sat 2015 Practice Test #1 Answer Explanations

Choice A is correct.
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D 
t
gives 
Dơ
t
. Then dividing both sides of 
Dơ
_
Dơ
t
E\JLYHV
t
= 
.

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Choices B, C, and D are incorrect and could arise from errors in 
rewriting 
D 
t
)RUH[DPSOHFKRLFH%FRXOGUHVXOWLI
is added to the left side of 
D 
t
and subtracted from the 
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QUESTION 10 
Choice B is correct.
The air temperature at which the speed of a sound 
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IRUD
and then solving for 
t
in the given formula. Substituting 
IRUD
in the equation 
D 
t
JLYHV
t
. 
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t 
DQGWKHQGLYLGLQJERWKVLGHVRIWKHHTXDWLRQE\\LHOGV
t
= 
ơ
_
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Choices A, C, and D are incorrect and might arise from errors made when 
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or solving for 
t
in the equation 
D 
t 
or in rounding the result to the nearest integer. For example, choice C 
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QUESTION 11 
Choice A is correct.
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[ơƪ[ơJLYHVơƪ[
. Therefore, 
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if and only if 
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[ơƪ[ơLIDQGRQO\LI[LVJUHDWHUWKDQơ2IWKHFKRLFHVJLYHQ
RQO\ơLVJUHDWHUWKDQơDQGWKHUHIRUHFDQQRWEHDYDOXHRI[
. 
Choices B, C, and D are incorrect because each is a value of 
[
that is less 
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QUESTION 12