posted by bill .
A boy is pushing his sled up a snowy slope. The sled has a mass of 20.4 kg and weighs 200 N. The boy pushes with a constant force of 75 N. The sled travels a distance of 10 m and gains 3 m in height. When the sled reaches the top, it is traveling 2 m/s. What is the efficiency of the slope?