Periodic Inventory by Three Methods The units of an item available for sale during the year were as follows: Jan. 1 Inventory 10 units at $43 Feb. 17 Purchase 15 units at $44 Jul. 21 Purchase 4 units at $47 Nov. 23 Purchase 13 units at $48 There are 10 units of the item in the physical inventory at December 31 . The periodic inventory system is us cent and final answers to the nearest whole dollar, if required. a. Determine the inventory cost by the first-in, first-out method. b. Determine the inventory cost by the last-in, first-out method. c. Determine the inventory cost by the weighted average cost method