Branson Creek Middle School has decided to make fitness a key message to their students in the upcoming school year. As a result, they will be participating in a national fitness program. To participate, they must randomly select 15 students in the 5th grade and record their exercise time each day. The data (in minutes) are shown.
85, 80, 76, 78, 82, 88, 80, 80, 110, 85, 85, 82, 83, 88, 76
Determine which measure of variation to use to describe the spread of the data.