A block of mass 0.5 kg is pushed a distance x against a spring with k=450 N/m. When released the block slides along a frictionless horizontal surface to a point B, the bottom of

a vertical circular track of radius R=1 meter. The track is not smooth. When the block reaches point B, its speed is 12 m/s. It undergoes a constant 7 Newton force along the
track. What was the initial compression of the spring? What is the speed of the block at the top of the circular track? Does the block even reach the top or does it fall of on the
way up?