A cart of mass m starts at rest, and is attached to a spring of spring constant k compressed at a distance x from equilibrium. After being released it rolls to the right on a frictionless track and moves up the curve in the track, and reaches a maximum height h above its starting position. Represent this in an equation in terms of the provided variables (k, h) and gravity.

final 2kx option A mg 2kx2 m option B mg initial option C h 2mg kx k option D 2mg 00000 M option E ka2 mg