GFOA Exam CPFO Topic 4 Question 86 Discussion

The city of Mudville uses 1600 oil filters annually. The cost of placing an order is $5.00. The unit cost is $3.50. The carrying cost is 20 percent, and the carrying cost per unit is &0.70(0.20x$3.50). And, there are 255 working days per year, and each order requires three working days of lead time. What is the reorder point?