The following table shows the flow of inventory in chronological order. October 1 4 12 16 24 31 Beginning Inventory Purchase Purchase Sale Purchase Ending Inventory Units 150 400 800 1,300 400 450 $/unit 20 30 32 50* 42 * Selling price Instructions (1) Assume the company follows a perpetual system. Using FIFO method, compute the cost of goods sold, the value of ending inventory and gross margin. (2) Assume the company follows a perpetual system. Using the moving average-cost method, compute the cost of goods sold, the value of ending inventory and gross margin. (3) Assume the company follows a periodic system. Using the total average-cost method, compute the cost of goods sold, the value of ending inventory and gross margin.