Passage V
In a study of human sleep cycles, subjects in 4 different age groups performed a brief mental task at a scheduled time. Immediately following the task, their oral temperatures were taken and then the time for each subject to fall asleep was measured.
The results were averaged for each group. Figure 1 shows how the average time to fall asleep for the 4 groups varied with the time of day that the task was performed. Figure 2 shows:how the average oral temperature of 2 of the groups varied with the time of day that the task was performed.
23. Based on Figure 1, at which of the following times was the average time to fall asleep most similar for the 4 age groups?
Your Answer is
Correct Answer is B
Explanation
Look at figure 1 to see the point where all the curves meet. There are two such points in the figure, one of which is abscissa at 1:30 PM, and the ordinate average time to fall asleep of each curve is the same at this time (the abscissa of the other point is about 5:30 PM)