15-58. Disk A has a mass of 250 g and is sliding on a smooth horizontal surface with an initial velocity(VAh = 2 m/s. It makes a direct collision with disk B, which has a mass of 175 g and is originally at rest. If both disks are of the same size and the collision is perfectly elastic (e = 1),determine the velocity of each disk just after collision. Show that the kinetic energy of the disks before and after collisions the same.