Oahu Kiki tracks the number of units purchased and sold throughout each accounting period but applies its inventory costing method at the end of each month, as if it uses a periodic inventory system. Assume Oahu Kikis records show the following for the month of January. Sales totaled 290 units.

	Date	Units			Unit Cost			Total Cost
Beginning Inventory	January 1		140		$	80		$	11,200
Purchase	January 15		330			90			29,700
Purchase	January 24		250			110			27,500

Calculate the cost of ending inventory and cost of goods sold using the (a) FIFO, (b) LIFO, and (c) weighted average cost methods.