a company uses a perpetual inventory system. on may 1, beginning inventory consists of 10 items at a cost of $10 each. on may 3, 10 items are purchased at $12 each. on may 8, 12 items are sold. on may 15, 10 items are purchased at $14 each. using the weighted average cost method, cost of goods sold for the month ended may 31 is: multiple choice $228.00. $144.00. $132.00. $230.40.