The company is using perpetual inventory system and the following data are available for Trekking Company for the month of August: Date Activity August 1 purchases 10 units @ 91 Aug. 3 Purchases 15 units @ $106 Aug. 14 Sales 20 units Aug. 17 Purchases 20 units @ $115 Aug. 28 Purchases 10 units @ $119 Aug. 31 Sales 23 units Required Calculate cost of goods sold and cost of ending inventory under : 1. FIFO method 2. LIFO method 3. Weighted average