Zippy Shoe Company uses a periodic inventory system. Zippy purchased 420 pairs of shoes at $74 each in June, 995 pairs in August at $76 each, and 640 pairs in December at $79 each. Zippy sold 1,880 pairs of shoes during the year. Required: Calculate the company's ending inventory and cost of goods sold using the each of following inventory costing methods. FIFO LIFO Weighted Average.