$3\mathrm{.}3$ The setup time in a sequential batch production operation is $2\mathrm{.}0$ hr $,$ and the actual process. ing time is $1\mathrm{.}60$ min per cycle. Three parts are produced each cycle. No tool handling time is included in the cycle. Part handling time each cycle is $45$ sec $.$ It consists of the worket obtaining two starting work units from a parts tray, loading them into the machine, and then after processing, unloading the completed parts and placing them into the same tray. Each tray holds $24$ parts. When all of the starting work units have been replaced with completed parts, the tray of completed parts is moved aside and a new tray of starting units is moved into position at the machine. This irregular work element takes $4\mathrm{.}0$ min $.$ Batch quantity is $2,400$ units. Determine $($a$)$ average cycle time, $($b$)$ time to complete the batch, and $($c$)$ aver: age production rate.