1. A snowboarder (mass = 10kg) coasts on a smooth, frictionless hill that rises from one level to another. If the snowboarder's initial speed is 6 m/s, the snowboarder just makes it to the upper level and comes to rest. Find the height of the hill. 2. Assume friction to be negligible in the roller coaster shown at right. If the roller coaster cart (mass = 5kg) starts at rest at point A, find: a. The speed at the bottom of hill A. B. The speed at the top of hill B