E6-15 Inventory by three methods; cost of merchandise sold The units of an item available for sale during the year were as follows: Jan. 1 Inventory 42 units at $1 80 Apr. 10 Purchase 58 units at $1 95 Sept. 30 Purchase 20 units at $204 Dec. 12 Purchase 30 units at $210 There are 37 units of the item in the physical Inventory at December 31. The periodic inventory system is used. Determine the inventory cost and the cost of merchandise sold by three methods, presenting your answers in the following form: Cost Merchandise Merchandise Inventory Method Inventory Sold a. First-In, first-out b. Last-in, first-out c. Average cost