Waiting Line Models

How do I answer these questions

Marty's Barber Shop has one barber. Customers have an arrival rate of 2.6 customers per hour, and haircuts are given with a service rate of 2 per hour. Use the Poisson arrivals and exponential service times model to answer the following questions:

What is the probability that one customer is receiving a haircut and one customer is waiting? (Round your answer to four decimal places.)

P₂ =

What is the probability that one customer is receiving a haircut and two customers are waiting? (Round your answer to four decimal places.)

P₃ =

What is the probability that more than two customers are waiting? (Round your answer to four decimal places.)

P(More than 2 waiting) =

What is the average time a customer waits for service? (Round your answer to four decimal places.)

W_q = minutes