Chapter 8 Inventories and the Cost of Goods Sold Rogers Products uses a periodic inventory system. The company's records show the beginning inventory of PH4 oil filters on January 1 and the purchases of this item during the current year to be as follows: Jan. 1 Beginning inventory Feb. 23 Purchase Apr. 20 Purchase May 4 Purchase Nov. 30 Purchase Totals ... 90 units @ $3.00 $ 270.00 120 units @ $3.50 420.00 300 units @ $3.80 1,140.00 400 units @ $4.00 1,600.00 190 units @ $5.00 950.00 1.100 units $4,380.00 ... a. A physical count indicates 200 units in inventory at year-end. Determine the cost of the ending inventory on the basis of each of the following methods of inventory valuation. (Remember to use periodic inventory costing procedures.) Average cost. b. FIFO. LIFO. d. Which of the above methods (if any) results in the same ending inventory valuation under both periodic and perpetual costing procedures? Explain. c