1. a) As a ball is moving vertically upward from the ground, is the gravitational potential energy (PE) increasing, decreasing, or remaining constant? (Assume the ground is the reference level.) b) After the ball has reached maximum height and is falling, is the gravitational potential energy increasing, decreasing, or remaining constant? hee leasing c) Write the equation for PE as a function of time. (Hint: Substitute the kinematic equation for y in one dimension into the PE equation.) PE=mah (d) Sketch a graph of the gravitational APE (J) potential energy vs. time for the entire trip of the ball. + Time (s) 2. For the ball in problem 1, graph the kinetic energy of the ball and the total energy for the ball during its trip. The magnitudes should correspond with the graph in problem Id. AKE (J) E total (J) + Time (s) + Time (s)