3. (2 points) Use queueing theory. National Bank is trying to decide how many drive-in teller windows to open on a busy Saturday. Manager Tod Eschenbach estimates that customers arrive at a rate of 1 = 16 per hour and that each teller can service u = 20 customers per hour. a. What is the optimum number of teller window(s) to open if the manager wants average number of customers in line is less than 0.05 customers? [Use table D.5) b. What is the average waiting time in the queue for the above optimum scenario (in minutes)