A large shopping area is considering opening an information desk that one employee will staff. Since related businesses have shared information, it is thought that eighteen customers will come to the desk every hour. Answering a question takes about two minutes on average. Assuming that arrivals are Poisson distributed and answer times are exponentially distributed, what is the average number of customers waiting in line to get information?
a. 2.75
b. 1.5
c. 0.9
d. 3.25
e. 2.0
