Periodic Inventory by Three Methods The units of an item available for sale during the year were as follows: Jan.1 Inventory 8 units @ $40 Feb. 17 Purchase 9 units @ $41 Jul. 21 Purchase 5 units @ $42 Nov. 23 Purchase 16 units @ $43 There are 8 units of the item in the physical inventory of December 31. The periodic inventory system is used. Determine the inventory cost under each of the following methods. Round interim calculations and the final answer to the nearest whole dollar. a. Determine the inventory cost by the first-in, first-out method.