An automated car wash serves customers with the following serial process: pre-treat, wash, rinse, wax, hand dry. Each of these steps is performed by a dedicated machine except for hand-dry step, which is performed manually on each car by one of 5 workers. The steps of the process have the following process times: -pretreat: 3 minute per car -wash: 3 minutes per car -rinse: 4 minutes per car wax: 4 minutes per car hand dry: 13 minutes per car a. If the car was has a demand of 19 cars per hour, what is the flow rate of the process? b. if the car wash has a demand of 15 cars per hour, what is the utilication of the machine that performs the wax process?