The diagram shows a block that is sliding down a frictionless hill. Diagram is not to scale. Refer to the above diagram to answer this question. The above diagram shows a 6.20 kg block sliding down a frictionless hill. At the instant the block passes over a point at the tip of 51, it has a speed of 1.71 m/s and is 3.96 m above the base of the hill. What is the mechanical energy of the block at that instant