Rockin’ Rocks offers two types of indoor climbing walls, the Challenge and the Psycho. There is one Challenge wall and 4 Psycho walls. There are two types of customers: Recreational and Expert. Recreationals do the Challenge wall in 10 minutes and then the Psycho wall in 30 minutes. Experts only do the Psycho wall and they take 15 minutes. Recreationals arrive at the rate of 7 per hour. Experts arrive at the rate of 3 per hour.

(a) What is the implied utilization of each wall? 

(b) What are the actual and maximum flow rates of Recreationals and Experts?