Repair calls are handled by one repairman at a photocopy shop. Repair time, including travel time, is exponentially distributed, with a mean of 21 hours per call. Requests for copier repairs come in at a mean rate of 2.4 per eight-hour day (assume Poisson). Determine the following: 0. The average number of customers awaiting repairs. (Round your answer to 2 decimal places.) b. System utilization. (Round your answer to 2 decimal places.) Answer is complete and correct. c. The amount of time during an eight-hour day that the repairman is not out on a call. (Round your onswer to 2 decimal ploces.) Answer is complete and correct. d. The probability of two or more customers in the system. (Do not round intermediate calculations. Round your onswer to 4 decimal places.)