4. Christiantina-Drill Company has a usage demand of 10300 oil filters for the span of a year, and this usage is relatively constant throughout the year. These oil filters are purchased from a dealer 520 miles away for $55.50 each unit, and it takes 8 days from order to receipt of items. The holding cost per unit per year is 22% of the unit cost and the ordering cost per order is $43.5. There are 300 working days per year