Judith Thompson is the manager of the student center cafeteria. She is introducing pizza as a

menu item. The pizza is ordered frozen from a local pizza establishment and baked at the

cafeteria. Judith anticipates a weekly demand of $10$ pizzas. The cafeteria is open $50$ weeks a

year, $5$ days a week. The ordering cost is $$15,$ and the holding cost is $$0\mathrm{.}40$ per pizza per year.

What is the optimal number of pizzas Judith should order?