Problem $18-1$ part A $($Algo$)$

A single$-$server system has an arrival rate of $12$ customers per hour, and a service rate of $15$ customers per hour. Both rates are Poisson distributed.

a$.$ What is the system utilization? $($Round your answer to $2$ decimals.$)$

b$.$ What is the average number of customers waiting for service? $($Round your answer to $2$ decimals.$)$

c$.$ What is the average time customers wait in line for service? $($Round your answer to $3$ decimals.$)$