4. A billiard ball of mass m = 0.250 kg hits the cushion of a billiard table at an angle of G1 = 66.0 at a speed of v1 = 27.2 m/s. It bounces off at an angle of 02 = 71 .0 and a speed of v2 = 10.0 m/s. (a) What is the magnitude of the change in momentum of the billiard ball? (b) In which direction does the change of momentum vector point? (Let up be the +y positive direction and to the right be the +x positive direction.) {5.26 kg m/s, 137 (counterclockwise from the +x-axis)} (picture from Haliday and Resnick book