A wheel free to rotate about its axis that is not frictionless is initially at rest. A constant external torque of +53 N·m is applied to the wheel for 22 s, giving the wheel an angular velocity of +610 rev/min. The external torque is then removed, and the wheel comes to rest 120 s later. (Include the sign in your answers.) (a) Find the moment of inertia of the wheel. (b) Find the frictional torque, which is assumed to be constant.