A tennis ball is a hollow sphere with a thin wall. It is set rolling without slipping at 4.13 m/s on a horizontal section of a track as shown in the figure below. It rolls around the inside of a vertical circular loop of radius r = 48.0 cm. As the ball nears the bottom of the loop, the shape of the track deviates from a perfect circle so that the ball leaves the track at a point h = 16.0 cm below the horizontal section.
(a) Find the ball's speed at the top of the loop.
(b) Find its speed as it leaves the track at the bottom.