The manager of Hippon Drug Store is remodeling his facility and is considering three ways of the organizing his branded-items business. The first way is to use a fast clerk to wait on all customers. Suppose such a clerk serves customers exponentially at the average rate of two minutes per customer. The second way is to utilize two moderately fast clerks to wait on all customers. Suppose each serves customers exponentially at the average rate of four minutes per customer. The 3rd way is to employ a self-service system in which each customer waits on himself. Self-service, at the average rate of 6 minutes, is slower than clerk service. The manager wants to compute the average number of the customers in store, the average time each squanders in the store, and the average time each spends waiting for the service, under each way of organizing. Suppose that customers arrive completely randomly, one at a time, at a rate of 15 per hour. Compute the operating characteristics of interest to the manager.