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 following 1. Determine the inventory on March 31 and the cost of goods sold for the three-month period, using the first-in, first-out method and the periodic inventory system. Inventory, March 314 Cost of goods sold \$ 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 $ 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 319 Cost of goods sold $ 4. Compare the gross profit and the March 31 inventories, using the following column headings. For those boxes in which you must enter subtracted or negative numbers use a minus sign