Benny the Barber owns a one-chair shop. At Barber college, they told Benny that his customers would exhibit a Poisson arrival distribution and that he would provide an exponential service distribution. Benny the Barber is considering the addition of a second chair. Customers would be selected for a haircut on a FCFS basis from those waiting. Benny has assumed that both barbers would take an average of 10 munutes to give a haircut, and that business would remain unchanged with customers arriving at a rate of three per hour. a. what is the average number of customers waiting? b. What is the average time a customer waits in line. c. what is the average time a customer is in the shop?