Determine the power rating of the motor in an elevator system. The elevator (with a full load) weights 2000 kg and is required to move upward 2 m/sec at constant speed. The lifting mechanism is 80% efficient (i.e., 20% of the power generated by the motor is wasted in the mechanism, e.g., for overcoming friction). What is the minimum output power rating in HP of the motor that meets the requirement?