Question B2 (30 pts): Customers arrive to Lincoln Savings Bank (LSB) with an average rate of 3 customers per minute. The average time a teller takes to serve a customer is 5 minutes. Standard deviation of customer inter-arrival time is 1.5 minutes and standard deviation of service time is 3 minutes. LSB employs 20 tellers. All customers form a single waiting line and can be served by any of the tellers in a first-come-first-serve basis as tellers become available. For simplicity, assume that there are no group arrivals, there is enough waiting space for all customers, and none of the customers abandon the line.

B2(a) - (5pts): What percent of the time a teller is busy with serving to a customer?

B2(b) - (10pts): On average, how many customers wait in the line?

B2(c) - (5pts): On average, how much time a customer spends waiting in the line?

B2(d) - (10pts): LSB estimates that for every hour a customer spends waiting in the line, LSB loses $60 due to customer dissatisfaction and losing future business. A teller is paid $20 per hour. Calculate the total hourly waiting and capacity cost generated by LSB.