a 3.7 kg box of running shoes slides on a horizontal frictionless table and collides with a 2.4 kg box of ballet slippers initially at rest on the edge of the table, at height h = 0.33 m. The speed of the 3.7 kg box is 4.1 m/s just before the collision. If the two boxes stick together because of packing tape on their sides, what is their kinetic energy just before they strike the floor?