1) Lila Battle has determined that the annual demand for number 6 screws is 150,000 screws. Lila, who works in her brothers hardware store, is in charge of purchasing. She estimates that it costs $10 every time an order is placed. This cost includes her wages, the cost of the forms used in placing the order, and so on. Furthermore, she estimates that the cost of carrying one screw in inventory for a year is 3 cents. Assume that the demand is constant throughout the year. (30 points)

a) How many number 6 screws should Lila order at a time if she wishes to minimize total inventory cost?

b) How many orders per year would be placed? What would the annual ordering cost be?

c) What would the average inventory be? What would the annual holding cost be?

d) What would the annual inventory cost be? e) Draw a plot of annual costs (ordering cost, holding cost, and inventory cost) as a function of order quantity.