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 Purchase 20 units at $360 260 units at $342 Aug. 13 $7,200 88,920 14,280 Nov. 30 Purchase 40 units at $357 320 units Available for sale $110,400 There are 57 units of the item in the physical inventory at December 31. The periodic inventory system is used. Determine the inventory cost using (a) the firse-in, first- out (FIFO) method; (b) the last-in, first-out (LFO) method; and (c) the weighted average cost method 3. First in, first-out (FIFO) method b. Last-in, first-out (LIFO) method Weighted average cost method