Periodic inventory by three methods The beginning inventory at Midnight Supplies and data on purchases and sales for a three-month period ending March 31 are as follows: 1. Determine the inventory on March 31 and the cost of goods sold for the three-month period, using the firstin, first-out method and the periodic inventory system. Inventory, March 315 Cost of goods sold 5 2. Determine the inventory on March 31 and the cost of goods sold for the three-month period, using the last-in, first-out method and the periodic inventory system. Inventory, March 31 : Cost of goods sold 5 3. Determine the inventory on March 31 and the cost of goods sold for the three-month period, using the weighted average cost method and the periodic inventory system. Round the weighted average unit cost to the nearest cent. Inventory, March 31