The table below shows data from a survey about the amount of time students spend doing homework each week. the students were either in college or in high school:

high low q1 q3 iqr median mean σ
college stu 50 6 8.5 17 8.5 12 15.4 11.7
high school 28 3 4.5 15 10.5 11 10.5 5.8

which of the choices below best describes how to measure the spread of this data?

a. both spreads are best described with the iqr.
b. both spreads are best described with the standard deviation.
c. the college spread is best described by the iqr. the high school spread is best described by the standard deviation.
d. the college spread is best described by the standard deviation. the high school spread is best described by the iqr.