Problem 25 (Plug-n-chug). The motor unit A is used to elevate the 300-kg cylinder at a constant rate of 2 m/s. If the power meter B registers an electrical input

of 2.20kW, calculate the combined electrical and mechanical efficiency e of the system. Round your answers to two decimal places. (а) 0.34 (b) 0.57 (c) 0.72 (d) 0.89 (e) None of these