In Fig. P1.66, determine the work rate by the air at the instant shown if Vpiston = 10 m/s, the torque T=20 Nm, the velocity gradient at the belt surface is 100 s-1 ,and the pressure acting on the piston is 400 Pa. the belt is 80 cm x 50 cm and the 40-cm-high rectangular piston is 50 cm deep (into the paper)