posted by bec .
A child on a beach kicks a beach ball, giving it an initial velocity of 4.0 m/s. It was sitting on the ground when given the kick. The ball lands on the beach 5m away and closer to the ocean, with a speed of 1.6m/s just before it hits. the final landing place is 1.2 m lower than the place where the ball was kicked. the mass of the ball is .40kg. How much work did air friction do on the ball during the trip?