consistently higher than the dotted, suggesting that Water can withstand higher frequencies,
eliminating (A) and (B). Then note the P-values on the right side of the graph. According to
the graph, these P-values increase with increasing sound pressure level, so in order to
increase the sound pressure level, we will want the highest possible P-value, which in the
list of remaining answer choices is 10−1 %, as in (D).
38 . G Use POE. According to this question, some change happens at high frequencies. Accordingly,
whichever graph we choose will need to show a change at high frequency, rather than low
frequency. Based on this information alone, we can eliminate (F) and (H). The dotted curve
(“after hearing loss”) should indicate some kind of hearing loss at high frequencies, so it
should show a curve that does not quite reach the highest frequencies, as only (G) does. If
you selected (J), you may have reversed the two curves.
39 . A The frequency of 10^4 cyc/sec doesn’t appear on the graph, but according to Figure 1, the
absolute threshold of hearing is around 10^3 cyc/sec. The pain threshold of hearing is within
the absolute threshold, so if 10^4 cyc/sec isn’t within the absolute threshold, it won’t be within
the pain threshold either. Think of it this way: In order for something to hurt when you hear it,
you need to be able to hear it first. Therefore, only (A) can work because it is the only
answer choice with a reason consistent with the information in Figure 1.
40 . G Use POE. If you’re unsure whether to answer yes or no, check the reasons. Use Figure 1.
Frequency appears on the x-axis, and Pressure appears on the y-axis. According to the lines
showing the pressure in Air and in Water, the increasing frequency has no effect on the
pressure values. Eliminate (F) and (H). Therefore, the pressure does not depend on the
frequency, making (G) the correct answer.
