Physics question i need help!?

Starting at the top of a steep, icy track, a rider jumps onto a sled and proceeds-belly down and head first- to slide down a track. The track has fifteen turns and drops 104 m in elevation from top to bottom. (A) In the absence of nonconservative forces, such as friction and air resistance, what would be the speed at the bottom of the track? ume that the speed of the rider at the beginning of the run is relatively small and can be ignored. (B) In reality, the best riders reach the bottom with a speed of 35.8 m/s. How much work is done on an 86 kg rider and sled by nonconservative forces? Thank you for any help!!!