Periodic Inventery by Three Metheds The units of on item avalable for sale charing the year were as follons! a. Deterimine the invertery cost by the firat-in, first - eut method. b. Daterivine the inventary cost by the lanc in. finatious mathed. c. Outermse the imventory cost by the weighted average cast method, Round average unit cost to the nearest cent and final answers to the nearest whele soltar, if required