Periodic Inventory by Three Methods The units of an item available for sale during the year were as follows: Jan. 1 Inventory Feb. 17 Purchase Jul. 21 Purchase Nov. 23 Purchase 1,040 units $126 1,435 units @ $128 1,600 units @ $130 1,150 units @ $130 There are 1,225 units of the item in the physical inventory at December 31. The periodic inventory system is used. Do not round Intermediate calculation and round final answer to nearest whole value 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