In some ordering problems, like the one for Sams Bookstore, whenever demand exceeds existing inventory, the excess

Question:

In some ordering problems, like the one for Sam’s Bookstore, whenever demand exceeds existing inventory, the excess demand is not lost but is filled by expedited orders–at a premium cost to the company. Change Sam’s model to reflect this behavior. Assume that the unit cost of expediting is $40, well above the highest regular unit cost.