help with poisson arrivals and exponential service times

5 points) A bank is considering opening two drive-through windows for customerservice. Customers are estimated to arrive at the average rate of 15 per hour. Thetellers who work at the windows are assumed to be identical, and can servicecustomers at the average rate of one every six minutes. Assume Poisson arrivals andexponential service times. a. Find the average number of customers in the waiting line (waiting but not beingserviced). b. Find the average waiting time in the system (including waiting in line and inservice). 0. Suppose that now the inter-arrival times are deterministic at the same rate; thatis, every hour exactly 15 customers arrive at the bank. Do you think your answer in (b) will become larger, or smaller, or remain the same, and why? Nocalculation needed.