Goodluck uses a perpetual system. Required: 1. Under a perpetual inventory system, determine the cost assigned to ending inventory and cost of goods sold under (a) weighted average cost method and (b) FIFO method. (For weighted average cost method, round to two decimal places for average cost per unit and round to the nearest dollar for all other answers.) Please show your calculations in a table as follows for both 1. (a) and 1. (b): (12 marks) 2. Calculate the goods available for sale and total sales. Show your calculation process. (4 marks) 3. If costs of inventory are decreasing, compared weighted average to FIFO method, which method of inventory valuation yield the lower cost of goods sold and explain the reason. (4 marks)