Weighted Average Cost Flow Method Under Perpetual Inventory System The following units of a particular item were available for sale during the calendar year: Jan. 1 Inventory 10,000 units at $75.00 Mar. 18 Sale 8,000 units May 2 Purchase 18,000 units at $77.50 Aug. 9 Sale 15,000 units Oct. 20 Purchase 7,000 units at $80.25 The firm uses the weighted average cost method with a perpetual inventory system. Determine the cost of merchandise sold for each sale and the inventory balance after each sale. Present the data in the form illustrated in Exhibit 6. Round unit cost to two decimal places, if necessary.