Problem 6-1A Calculate ending inventory and cost of goods sold for four inventory methods (LO6-3) The following information applies to the questions displayed below. Sandra's Purse Boutique has the following transactions related to its top-selling Gucci purse for the month of October. Sandra's Purse Boutique uses a periodic inventory system. Date October 1 October 4 October 10 October 13 October 20 October 28 October 30 Transactions Units Cost per Unit Total Cost. Beginning inventory Sale Purchase Sale Purchase Sale Purchase $900 910 920 930 $5,400 4,550 3,680 6,510 $20,140 6 5