Periodic Inventory Using FIFO, LIFO, and weighted Average Cost Methods The units of an item available for sale during the year were as follows: Jan. 1 Inventory 12 units at $5,400 $64,800 Aug. 7 Purchase 18 units at $6,000 108,000 Dec. 11 Purchase 15 units at $6,480 97,200 Available for sale 45 units $270,000 There are 14 units of the item in the physical inventory at December 31. The periodic inventory system is used. Determine the inventory cost using (a) the first-in, first-out (FIFO) method; (b) the last-in, first-out (LIFO) method; and (c) the weighted average cost method. a. First-in, first-out (FIFO) method SL b. Last-in, first-out (LIFO) method c. Weighted average cost method