ABC Hardware Store is a very small hardware store in a small town. It has just gotten a new manager, and she has called you in to observe the operations of the store and propose ways to increase profits, decrease costs, and improve efficiencies. You are in the role of a consultant.

The hardware store has $$all the basics$$ in terms of supplies, but their niche is that they have the best Items A$,$ B$,$ and C in the state. In fact, very few hardware stores even carry these items. People come from all over to get them, and much of the company$$s good reputation is because of having these items and the ability to make them. In fact, they sell at least $40$ total of these items every week $($varying combinations of A$,$ B$,$ and C$).$

The store is open $7$ days a week from $6$AM$-6$PM$.$

As you enter the store at about $10$AM$,$ you see three checkout areas each with their own register, one self$-$checkout area, and Margie, the only cashier working, has seven people in line at one of the three registers. The other two registers are closed. The self$-$checkout machine is currently out of order. The customers at the end of the line are not happy.

To keep the checkout area organized, there is a single line corral, so each customer gets the next available cashier $$ if more than one would be working. You witness the last person in line returning their item to the shelf and leaving without purchasing an item. That person was not interested in waiting.

Throughout the day, you notice that Margie$$s line usually has between $4$ and $7$ people in it$,$ and she is working as fast as she can. On average, a new person gets in line every $3$ minutes, and it takes $3\mathrm{.}5$ minutes to serve the customer. When the line gets $$bad enough,$$ Margie calls other employees to come to the front of the store if they can, and they will usually place themselves at the other registers, and stay there until the line goes down. They return to the floor when the line is more manageable. On average, there are two floor employees working who Margie can call. Margie has asked for another cashier, but the previous manager said that their current system was fine.

As you continue to roam the store throughout the day, you arrive at the station that creates items A$,$ B$,$ and C with specialized machines. There are machines which make each item from separate parts $($which are housed in the storeroom$),$ and there are $3$ machines in all. You learn the following about who is trained to operate the machines $($Brett$,$ Myra, and Candice$),$ how long it takes to make a single item, and the number of hours each employee works each week at the machines as opposed to on the sales floor. When an employee or manager notices that they are running low on an Items A$,$ B$,$ and$/$or C$,$ whoever is there $($Brett$,$ Myra, or Candice$)$ gets pulled off the floor and goes to a machine to make the items.