The Sea View Resort Uses a Multiple-Channel Queue Registration System $\lambda$

The Sea View Resort uses a multiple-channel queue registration system. If the average service time is 8 minutes, there are three registration clerks, and guests arrive at the rate of one every 5 minutes, find
a. $\lambda$ and $\mu$ .
b.the probability all three clerks are idle.
c.the probability a guest will have to wait.
d.the average time a customer is in line.
e.the average number of customers in line.