"Baseball Bias"

Bill is riding in a railroad car, throwing a ball against the car wall. The train is moving at 20 m/s to the right. Bill is throwing the ball at 8 m/s to the left. According to Bill, his 0.145 kg baseball has 4.64 joules of kinetic energy. His brother is standing on the ground disagreeing. According to him the baseball has 10.44 joules of kinetic energy. Who is right?