Suppose Joe orders the quantity from part $($c$)$ that minimizes the sum of the ordering and holding costs each time he places an order with the supplier. What is the annual cost of the EOQ expressed as a percentage of the annual purchase cost?

Note: Round your answer to $2$ decimal places.

If Joe$$s supplier only accepts orders that are an integer multiple of $1000$ gallons, how much should Joe order to minimize ordering and holding costs per gallon?

Joe$$s supplier offers a $3\mathrm{.}00$ percent discount if Joe is willing to purchase $8000$ gallons or more. What would Joe$$s total annual cost $($purchasing$,$ ordering, and holding$)$ be if he were to take advantage of the discount?