A Suburban Specialty Restaurant Has Developed a Single Drive-Thru Window

Multiple Choice

A suburban specialty restaurant has developed a single drive-thru window.Customers order,pay,and pick up their food at the same window.Arrivals follow a Poisson distribution while service times follow an exponential distribution.If the average number of arrivals is 6 per hour and the service rate is 2 every 15 minutes,what proportion of the time is the server busy?

A) 0.25
B) 0.50
C) 0.75
D) 2.25
E) 3.00