Since the deregulation of the airline industry, fierce competition has forced Global Airlines to reexamine their operations for efficiency and economy. As part of their campaign to improve customer service, they have focused on passenger check-in operations at the terminal. Global operates a common check-in system wherein passengers for all Global's flights line up in a single "snake line." The arrival rate is estimated to be 66 passengers per hour. The check-in process takes an average of six minutes. Agents are paid $23 an hour. The customer relations department estimates that every minute a customer spends waiting in line to be checked in, it costs Global $1 due to missed flights, customers' dissatisfaction, and loss of future business. Assume that interarrival and service times are exponentially distributed.

a.
How many agents should Global staff?

b.
What is the average waiting time in line? (Do not round intermediate calculations. Round your answer to 3 decimal places.)

c.
What is the average number of customers in the system? (Do not round intermediate calculations. Round your answer to 2 decimal places.)

d.
What is the average number of customers that are in service? (Do not round intermediate calculations. Round your answer to 1 decimal place.)