A 60 kilogram kid slides down a water slide that is at an angle of 20 degree from the horizontal. He starts off 8.0 m high (vertically) with a velocity of 2.0 m/s. At the bottom, he has a speed of 9.0 m/s.
a) Determine the force of friction the kid experiences throughout the slide?
b) Find at what vertical height will the child have achieved a speed of 5.0 m/s?