8b.1 A 2.0-kg frictionless cart is moving at 6.0- m/s on a horizontal surface just before it starts up a ramp that rises vertically 1.50 m from top to bottom. Set zero height to be at the bottom of the slide. (a) Calculate the kinetic energy, potential energy and mechanical energy of the cart as it starts up the ramp. [Answer: 36 J, 0, 36 J] (b) Calculate the kinetic energy, potential energy and mechanical energy when it reaches the top of the ramp. [Answer: 6 J, 30 J, 36 J] (c) Calculate the speed of the cart when it reaches the top of the ramp. [Answer: 2.45 m/s]