Consider a$$ three$-$firm supply chain consisting of a$$ retailer, manufacturer, and supplier. The$$ retailer's demand over an$8-$week period was $105$ units each of the first $2$ weeks, $220$ units each of the second $2$ weeks, $310$ units each of the third $2$ weeks, and $410$ units each of the fourth $2$ weeks. The following table presents the orders placed by each firm in the supply chain.$$ Notice, as is often the case in supply chains due to economies of$$ scale, that total units are the same in each$$ case, but firms further up the supply chain$($away from the$$ retailer$)$ place$$ larger, less$$ frequent, orders.