The Robotics Manufacturing Company operates an equipment repair business where emergency jobs arrive randomly at the rate of two jobs per $8-$hour day. The company's repair facility is a single$-$server system operated by a repair technician. The service time varies, with a mean repair time of $3\mathrm{.}2$ hours and a standard deviation of $2\mathrm{.}1$ hours. The company's cost of the repair operation is $$28$ per hour. In the economic analysis of the waiting line system, Robotics uses $$38$ per hour cost for customers waiting during the repair process.