28. Question 28 refers to the following information.
The 22 students in a health class conducted an experiment in which they each recorded their pulse rates, in beats per minute, before and after completing a light exercise routine. The following dot plots display the results.
Begin skippable figure description.
The figure presents 2 dot plots. The first dot plot is labeled “Beats per minute before exercise.” The second dot plot is labeled “Beats per minute after exercise.”
For the dot plot labeled “Beats per minute before exercise,” the numbers 56 through 88, in increments of 4, are indicated on the number line with the following data points.
56 beats per minute, 1 dot.
60 beats per minute, 0 dots.
64 beats per minute, 1 dot.
68 beats per minute, 5 dots.
72 beats per minute, 8 dots.
76 beats per minute, 5 dots.
80 beats per minute, 1 dot.
84 beats per minute, 0 dots.
88 beats per minute, 1 dot.
For the dot plot labeled “Beats per minute after exercise,” the numbers 80 through 112, in increments of 4, are indicated on the number line with the following data points.
80 beats per minute, 2 dots.
84 beats per minute, 2 dots.
88 beats per minute, 3 dots.
92 beats per minute, 3 dots.
96 beats per minute, 2 dots.
100 beats per minute, 3 dots.
104 beats per minute, 3 dots.
108 beats per minute, 2 dots.
112 beats per minute, 2 dots.
End skippable figure description.
Question 28.
Let and be the standard deviation and range, respectively, of the data before exercise, and let and be the standard deviation and range, respectively, of the data after exercise. Which of the following is true?