44. Calculate At an amusement park, a swimmer uses a water slide to enter the main pool. If the swimmer starts at rest, slides without friction, and descends through a vertical height of 2.31 m, what is her speed at the bottom of the slide? 45. Calculate A 0.21-kg apple falls from a tree to the ground, 4.0 m below. Ignoring air resistance, determine the apples kinetic energy, KE, the gravitational potential energy of the system, PEgravity, and the total mechanical energy of the system, E, when the apples height above the ground is 3.0 m. 46. Analyze You throw a baseball glove straight upward to celebrate a victory. Its initial kinetic energy is KE, and it reaches a maximum height h. What is the kinetic energy of the glove when it is at the height h/2