A unicylist is riding down the princess highway at a constant velocity. The free body diagram of his wheel is shown below. The rider is applying a torque (360 Nm) to the 0.75 m radius wheel which is opposed by the friction force Fr. If the coefficient of static friction is 0.5, and the coefficient of kinetic friction is 0.2, what is the combined mass of the wheel and rider in kg? Assume the wheel is not slipping (but would slip if any additional torque were applied), and assume gravitational acceleration is 10 m/s^2.