Periodic Imventory by Three Methods The anits of an item available for sale during the year were as follows: There are 6 units of the nem in the physicat inventory at December 31. The penodic inventory system is used. Mound average unit cost to the nearest cent and finat aiswers to the fichasest whole dollar, if required W. Determine the inventory cost by the first in, first out method b. Detaimine the inventory cost by the linat in. firstiost method. Dotemmine the inyentory cost by the weightied average cont method