Repair calls for Xerox copiers in a small city are handled by one repair person. Repair duration, 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). Assume infinite source.
The average number of copiers waiting for repair.
The amount of time during an eight-hour day that the repair person is not out on a call.
The probability of two or more copiers in the system (waiting for or being repaired).
The probability that a copier waits more than four hours for repair to begin.