1. The problem statement, all variables and given/known data Two girls are playing baseball in a park. The batter hits the 400-g ball with a speed of 20.0 m/s. It travels over the park's fence that is 4.00 m high. Assuming that the ball loses half of its energy to air resistance, at what speed does the ball travel over the fence? 2. Relevant equations Ek = 0.5*m*v^2 Ep = m*p*h 3. The attempt at a solution 0.5*(0.4Kg)*(20 m/s)^2 = 0.5 [(0.4Kg)(9.81 m/s^2)((4m) + 0.5(0.4Kg) Vf^2] My answer was wrong.