he materials manager for a billiard ball maker must periodically place orders for resin, one of the raw materials used in producing billiard balls. She knows that manufacturing uses resin at a rate of $50$ kilograms each day, and that it costs $$\mathrm{.}04$ per day to carry a kilogram of resin in inventory. She also knows that the order costs for resin are $$100$ per order, and that the lead time for delivery is four days. What is the economic order quantity for resin?