Required information [The following information applies to the questions displayed below.] Carlson Auto Dealers Inc. sells a handmade automobile as its only product. Each automobile is identical; however, they can be distinguished by their unique ID number. At the beginning of 2021 , Carlson had three cars in inventory, as follows: During 2021, each of the three autos sold for $78,000. Additional purchases (listed in chronological order) and sales for the year were as follows: 4. Calculate ending inventory and cost of goods sold assuming the average cost method and a periodic inventory system