Cathy Livingston, bartender at the Los Gactos Racquet Club, can serve drinks at the rate of one every 50 seconds. During a hot evening recently, the bar was particularly busy and every 55 seconds someone was at the bar asking for a drink.

a. Assuming that everyone in the bar drank at the same rate and that Cathy served people on a first-come, first-served basis, how long would you expect to have to wait for a drink?

b. How many people would you expect to be waiting for drinks?

c. What is the probability that three or more people are waiting for drinks?

d. What is the utilization of the bartender (how busy is she)?

e. If the bartender is replaced with an automatic drink dispensing machine (with a constant service time), how would this change your answer in part a?