Answer:
310 feet per mile marker
Explanation:
The average change will be the difference in elevation over the difference in mile markers. Randy’s elevation changed from 6220 feet to 8390 feet, which is a difference of
8390-6220=2170 feet. He started tracking at mile markers 6 to mile markers 13, which is a difference of
13-6=7 miles markers. The average change in elevation is 2170 feet / 7 mile markers = 310 feet per mile marker.