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 Transactions Beginning inventory Units Unit Cost 6 $ 810 Total Cost $ 4,860 4 Sale 4 October 10 Purchase 5 820 4,100 October 13 Sale 3 October 20 Purchase 4 830 3,320 October 28 October 30 Sale Purchase 840 5,880 $18,160 3. Using LIFO, calculate ending inventory and cost of goods sold at October 31.