Rocky Mountain Tire Center sells $$go$-$cart tires per year. The ordering cost for each order is $$$$,$ and the holding cost is $\%$ of the purchase price of the tires per year. The purchase price is $$$ per tire if fewer than tires are$$ ordered, $$$ per tire if or morebut fewer than tires are$$ ordered, and $$$ per tire if or more tires are ordered.

Part $2$

$$a$)$ How many tires should Rocky Mountain order each time it places an$$ order?

Rocky$$ Mountain's optimal order quantity is

$$

$8000$ units $($enter your response as a whole$$ number$).$

Part $3$

$$b$)$ What is the total cost of this$$ policy?

Total annual cost of ordering optimal order size$$$

$$

enter your response here $($round your response to the nearest whole$$ number$).$