3. For Project Crashing Practice the solved math problem 5 from Stevenson's Operation Management Book (Assignment) 4) Repair calls are handled by one repairman at a photocopy shop. Repair time, including travel time, is exponentially distributed, with a mean of two hours per call. Requests for copier repairs come in at a mean rate of three per eight- hour day (assume Poisson). Determine: 1. The average number of customers awaiting repairs. 2. System utilization. 3. The amount of time during an eight-hour day that the repairman is not out on a call. 4. The probability of two or more customers in the system. (Assignment) 5) A vending machine dispenses hot chocolate or coffee. Service time is 30 seconds per cup and is constant. Customers arrive at a mean rate of 80 per hour, and this rate is Poisson-distributed. Determine: a. The average number of customers waiting in line. b. The average time customers spend in the system. c. The average number in the system