Perpetual inventory using weighted average Beginning inventory, purchases, and sales for WCS12 are as follows: a. Assuming a perpetual inventory system and using the weighted average method, determine the weighted average unit cost after the October 22 purchase. Round your answer to two decimal places. $ per unit b. Assuming a perpetual inventory system and using the weighted average method, determine the cost of goods sold on October 29 . Round your "average unit cost" to two decimal places. $ c. Assuming a perpetual inventory system and using the weighted average method, determine the inventory on October 31 . Round your "average unit cost" to two decimal places. $