A company has started a phone service that uses overseas doctorsto provide emergency medical consultations. The responding doctorsare based in a country with low wages but with a highly skilledpool of physicians. Responding to each call takes on average 15minutes. At any given moment in time, there are 4 doctors overseason duty. Calls arrive every 5 minutes on average and standarddeviation of the inter-arrival time is 5 minutes. If no doctor isavailable overseas, the call is rerouted to the U.S. where a localphysician answers the question. A local physician is alwaysavailable to take a call. In this case, the firm pays $50 to thelocal physician.?

Now assume that the demand has increased to 20 calls per hourfor the overseas doctors. Responding to each call still takes onaverage 15 minutes. At any given moment in time, there are 4doctors overseas on duty. The coefficient of variation ofcustomers’ inter-arrival time is 1. If no doctor is availableoverseas, the call is rerouted to the U.S. where a local physiciananswers the question.

Q18. What is the number of calls directed to the doctors in theUS every hour?

Q19. The company has set a new goal to direct no more than 2calls per hour to the doctors in the US. How many doctors do theyneed overseas?