Problem 2 (Queueing Model) (30 points) A company has a central document-copying service. Arrivals can be assumed to fol- low a Poisson process, with a mean rate of 15 per hour. It can be assumed that service times are exponentially distributed. With the present copying equipment, the aver- age service time is 3 min. A new machine can be leased that has a mean service time of 2 min. The average wage of the people who bring the documents to be copied is $8 an hour. a. If the machine can be leased for $5 per hour more than the old machine, should the company replace the old machine