Previous records indicate that each of the 5 computer laser printers at the US Department of Energy, in Washington, DC, needs repair after about 20 hours of use. It has been determined that the breakdowns have a Poisson distribution. The single technician on call can service a printer in an average of 2 hours, following an exponential distribution. Printer downtime costs $120 per hour. Technicians are paid $25 per hour. Should the DOE hire a second technician?

2.) Joe Ferris is a stock trader on the floor of the New York Stock Exchange for Smith, Jones, Johnson and Thomas, Inc. Stock trading averages 20 per hour. Each order received by Joe requires an average of two minutes to process.

A.) What is the average service rate per hour?

B.) What percentage of orders will be processed in exactly 3 minutes?

C.) What is the average time an order must wait from the time Joe receives the order until it is finished processing (i.e., his response time)?

D.) What is the average number of orders that Joe has waiting to be processed?

E.) What percentage of the time is Joe processing orders?