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 30 pizzas. The cafeteria is open 45 weeks a year, 5 days a week. The ordering cost is $15 and the holding cost is $0.80 per pizza per year. What is the optimal number of whole pizzas Judith should order?