Please answer

On average, 200 passengers arrive per hour at a local airport. 80% of the customers utilize kiosks for check-in. The remaining 20% require the assistance of an agent. After check-in, all customers proceed to security control. At the airport, there are 10 kiosks and a customer spends on average three minutes to complete check-in at a kiosk. There are four check-in agents and customers spend on average five minutes with an agent. Finally, there are seven security officers and the security check takes 1.5 minutes per passenger. Assume that customer inter-arrival and service times are exponentially distributed and for all three types of services, customers join a single line and proceed to the next available server.

a. What is the average number of passengers at the airport?

b. What is the total throughput time of a customer who checks in at a kiosk?