A spring of negligible mass stretches 3.00 cm from its relaxed length when a force of 7.20 N is applied. A 0.480-kg particle rests on a frictionless horizontal surface and is attached to
the free end of the spring. The particle is displaced from the origin to x = 5.00 cm and released from rest at t = 0. (Assume that the direction of the initial displacement is positive.
Use the exact values you enter to make later calculations.)