I'm stuck on this question. I think it may be a bit easy but i still can't figure what im supposed to do. Heres the question. A horizontal sprinh, of force constant 12 N/m, is mounted at the edge of a lab bench to shoot marbles at the targets on the floor 93.0 cm below. A marble of mass 0.0083 kg is shot from the spring, which is initially compressed a distance of 4.0 cm. How far does the marble travel horizontal before hitting the floor? Can anyone please help me?