The units of an item available for sale during the year were as follows:

January 10 January 15	Inventory Sold	27 units @ $90 20 units
February 27 March 1	Purchase Sold	54 units @ $98 35 units
July 11 July 15	Purchase Sold	63 units @ $106 75 units
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 both ending inventory and cost of goods sold by (a) the first-in, first-out method, (b) the last-in, first-out method, and (c) the average cost method. Show your work?