solve please

121 Two blocks of mass 300 g and 200 g are moving to- ward each other along a horizontal frictionless surface with velocities of 50 cm.s ) and 100 cm.s ], respectively. a) If the blocks collide and stick together, find their final velocity. b) Find the loss of kinetic energy during the collision. c) Find the final velocity of each block if the collision is completely elastic. 7-22