The units of an item available for sale during the year were as follows. January 10 Inventory 27 units @ $90. February 27 Purchase 54 units @ $98. July 11 Purchase 63 units @ $106. November 13 Purchase 36 units @ $115. There are 50 units of the item in the physical inventory at December 31. The periodic inventory system is used. Determine the ending inventory cost ba (a) the first-in, first-out method. (b) the last-in, first-out method, (c) the average cost method