A movie theatre experiences the highest volume of ticket sales on fridays from 10:00 a.m. to 6:00p.m. Currently, there are three ticket windows serving their own line in front of each window. A consultant hired recently carried out a time study and found that the verbal communication between the customer and the salesperson takes three minutes on the average. The same study also revealed that there were no customers in the system 20% of the time. Based on Poisson arrival rates and exponential service times, answer the following questions. a) What is the arrival rate per hour at each line? c=3 b) How long on the average must a customer wait before the start of the service by the salesperson? c) What is the average length of each queue? d) What is the probability of finding at most two customers waiting in each queue