Rocky Mountain Tire Center sells 8 comma 000 ?go-cart tires per year. The ordering cost for each order is ?$40 ?, and the holding cost is 40 ?% of the purchase price of the tires per year. The purchase price is ?$22 per tire if fewer than 200 tires are? ordered, ?$19 per tire if 200 or? more, but fewer than 5 comma 000 ?, tires are? ordered, and ?$13 per tire if 5 comma 000 or more tires are ordered. ?a) How many tires should Rocky Mountain order each time it places an? order?