A tax consulting firm has three counters in its office to receive people who have problems concerning their income, wealth, and sales taxes. On average, 48 persons arrive in an 8-hour day. Each tax adviser spends an average of 15 minutes on an arrival. If the arrivals are Poissonly distributed and service times are exponentially distributed, find:
a) The average number of customers in the system.
b) The average number of customers waiting to be served.
c) The average time a customer spends in the system.
d) The average waiting time for a customer.
e) The number of hours each week (5-working day) a tax adviser spends performing his job.
f) The probability that a customer has to wait before he gets service.
g) The expected number of idle tax advisers at any specified time.