show all work please. not sure how to get this

The gross requirements for item Z are specified for the beginning of weeks 1 through 8 in the table that follows. Gross Requirements for Item z Week 1 2 3 4 5 6 7 8 180 90 180 0 360 0 90 90 Gross Requirement The lead time is 2 weeks. The current on hand inventory, at the beginning of week 1 is 360 units. If the order cost is $540 per order and the inventory cost is $3 per unit per period, and the order quantity is the computed part period (or a multiple of the computed part period) when it is necessary to place an order, what is the total cost for the 8 week period? Report as a whole number with no commas. Answer: X The correct answer is: 4590