S library has 10 copies of the Operations Management textbook. The interarrival time between rental requests for the textbook is 3 days, on average, with a standard deviation of 2 days. Assume that, if all copies are rented, students are willing to wait until there is a copy available. A copy is rented, on average, for 15 days, with a standard deviation of 5 days.

• What is the average number of textbooks that are rented out by students?
• What is the average time a student has to wait to rent a copy?
• How would the waiting time change if S library decides to limit all book rentals to exactly 14 days? Assume that if such a restriction is imposed, the average interarrival time will reduce to 2 days, with the standard deviation changing to 1.5 days.