A gear drive for a special-purpose, dedicated machine tool is being designed to mill a surface on a rough steel casting. The electric motor drive system must transmit 16-hp with a pinion speed of 900-rpm and an output speed between 110 and 115- rpm. The mill is to be used continuously, two shifts per day, six days per week for at least five years. Consider 20° full-depth teeth and a 99% reliability. The design power for the system, Pdes, is_________