A billiard ball of mass m = 0.250 kg hits the cushion of a billiard table and rebounds. The ball's velocity before it hits the cushion is 20.0 m/s making an angle of 60.0o with respect to the normal. The glancing blow leaves the ball with a velocity of 12.0 m/s at 71.0o to the other side of the normal.
(a) What is the magnitude of the change of momentum of the ball?
(b) What is the direction of the change of momentum?