The units of an item available for sale during the year were as follows: Jan. 1 Inventory 40 units at $165 $6,600 Aug. 13 Purchase 200 units at $180 36,000 Nov. 30 Purchase 60 units at $200 12,000 Available for sale 300 units $54,600 There are 75 units of the item in the physical inventory at December 31. The periodic inventory system is used. Determine the inventory cost using the (a) first-in, first-out (FIFO) method; (b) last-in, first-out (LIFO) method; and (c) weighted average cost method