3) A 2.5-kilogram block is released from rest at the top of a 0.5meter vertically high hill. It slides down and strikes a second block which is at rest with a mass of 3.6 kilograms. The two blocks stick together after the collision. The flat surface at the bottom does have friction and a constant force of friction of 5 N acts on the blocks. How far will the two bricks slide before coming to rest?