Infinite capacity single server queue with exponential arrivals and general distributed service (M/G/1)

Calculate the average waiting time (in minutes) in an M/G/1 queue if the arrival rate is 8 customers per hour and the service rate is 10 customers per hour, and the mean service time is 6 minutes.
Determine the utilization factor ('ρ') for an M/G/1 queue if the arrival rate is 6 customers per hour and the service rate is 8 customers per hour.
Find the probability that an arriving customer has to wait in an M/G/1 queue if the average arrival rate is 4 customers per hour and the average service rate is 6 customers per hour.
Calculate the average number of customers in the system for an M/G/1 queue if the arrival rate is 5 customers per hour and the service rate is 7 customers per hour.