Periodic Inventory Using FiFo, UFO, and Weighted Average Cost Methods The unils of an item avalable for sale during the year were as follows: There are 75 units of the item in the physical imventory at December 31 . The periodic inventory system is used. Determine the inventory cost using the (a) first-in, first: out (FIFO) method; (D) last-in, first-out (UIFO) method; and (c) weighted average cost method