The women’s department at Hector’s Department Store has a single checkout register. Customers…

  The women’s department at Hector’s Department Store has a single checkout register. Customers arrive at the register at the rate of 11 per hour. It takes the clerk, on average, 4 minutes to check out a customer.

 a. (**) On average, how many customers will be waiting to be checked out? Do you think this number is reasonable? Why or why not? b. (**) How long, on average, will a customer have to wait before the clerk starts serving him or her? Again, is this a reasonable time? If Hector’s decides to open another register, what are the trade-offs to consider?