An athlete at the gym holds a 3.0 kg ball in his hand. His arm is .70 cm long and has a mass of 4.0 kg. What is the magnitude of the torque about his arm if he holds his arm straight out his side, parallel to the floor. I did T=mgr since theta is zero so both the force of gravity on his arm and ball is down. So 7* 9.8*.70 where the mass is the mass of his arm + mass of the ball. I get 48 N-m but this is wrong the answer is 34 N-m. What am I doing wrong?