Brianna's Boutique has the following transactions related to its top-selling Gucci purse for the month of October. Brianna's Boutique uses a periodic inventory system. Total Cost $4,620 Date Transactions October 1 Beginning inventory October 4 Sale October 10 October 13 October 20 Purchase Sale Purchase October 28 October 30 Sale Purchase Units 6 Unit Cost $770 4 5 780 3,900 3 4 790 3,160 7 7 800 5,600 $17,280 Required: 1. Calculate ending inventory and cost of goods sold at October 31, using the specific identification method. The October 4 sale consists of purses from beginning inventory, the October 13 sale consists of one purse from beginning inventory and two purses from the October 10 purchase, and the October 28 sale consists of three purses from the October 10 purchase and four purses from the October 20 purchase.