posted by Angel .
A ski trail makes a vertical descent of 77 m. A novice skier, unable to control his speed, skis down this trail and is lucky enough not to hit any trees.
If the skier is moving at 17 m/s at the bottom of the trail, calculate the total work done by friction and air resistance during the run. The skier's mass is 74 kg.
I don't undertand how to do this am confused :/ please help!