Periodic imventory by three methods; cost of goods sold The units of an item avalable for sale during the year were as follows: There are 80 unts of the item in the physical inventery at December 31 . The perlodic inventory system is used. Determind the ending inventory cost and the cost of goods sole by three methods. In your calculations round average unit cost to the nearest cent, and round all other calculations and your finat answers to the nearest doltar. fenthes: rotkwiwas