Consider two bodies A and B of masses m1 and m2 moving along the same straight line in the same direction with velocities U1 and U2. The bodies A and B suffer a head on collision when they strike and continue to move along the same straight line with velocities V1 and V2 respectively. Assume the collision is elastic, a. Show that U1 + V1 = U2 + V2 b. Find the expression for V1 and V2 in terms of other parameters.​