Waterslides are nearly frictionless, hence can provide bored students with high-speed thrills. One slide for example in Jackson's Six Flags Great Adventure called the Aqua Speeder is 75.0 feet high, convert this to meters, then
(a) Determine the speed of a 40.0 kg man named Kevin at the bottom of such a slide, assuming no friction is present.
(b) If Kevin is clocked at 25 m/s at the bottom of the slide, find the work done on him by friction.