Suppose that a spring is attached to a wall. On the other end of the spring, it is attached to an object of 0.263kg. When the spring is compressed at a distance of 15cm, it holds an elastic potential energy of 20.0J. The horizontal surface has no friction; frictionless.

a) If the motion has an amplitude of 7.00cm and a period of 3.0s, where is the object and in what direction is it moving 0.45 seconds after it has passed the equilibrium position, moving to the left?
b) calculate the system's KE and PE In the moment expressed in part b
c) What force ( magnitude and direction) does the spring apply on the object when it is 3.50cm to the right of the equilibrium position, moving to the right?