A recent analysis at a Staples store by the store manager indicates that, during operating hours, there are 30 customers arriving every hour, with a standard deviation of inter-arrival times of 2 minutes. This arrival pattern is consistent throughout the day. The checkout is currently operated by one employee, who needs on average 1.85 minutes to check out a customer. The standard deviation of this checkout time is 3 minutes, primarily because of customers buying different numbers of items. a) If you assume that every customer buys at least one item (i.e. has to go to check out), what is the average time a customer has to wait in line before being served by the checkout employee? b) What is the total time a customer spends in line and at the checkout counter being served? c) What is the average number of customers who are in the system (i.e., either waiting or being served)? d) The manager decides that the waiting time is way too long and hires two more checkout clerks, for a total of three. What is the waiting time (in the line, before being served) in this new situation?