3 Accounting Volume 1,... x About Support EX 6-6 Perpetual inventory using FIFO and Beginning inventory, purchases, and sales data for watches are as follows: weighted average Inventory May 1 850 units at $112 Purchases May 8 Sales 19 320 units at $120 98 units at $132 May 10 600 units 15 405 units 30 172 units a. Inventory balance, May 31, $12,012 a. Assuming that a perpetual inventory system is used, costing by the FIFO method, determine the cost of goods sold for each sale and the inventory balance after each sale, presenting the data in the form illustrated in Exhibit 3, on page 310. b. Assuming that the perpetual inventory system is used, costing by the weighted average method, determine the cost of goods sold for each sale and the inventory balance after each sale, presenting the data in the form illustrated in Exhibit 4, on page 311. A Px