my answers have been incorrect and im not understanding this

Required information [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 Beginning inventory October 4 Sale October 10 October 13 October 20 October 28 October 30 Transactions Ending inventory Cost of goods sold Purchase Sale Purchase Sale Purchase Units Unit Cost 6 $810 4 5 3 4 7 7 820 830 840 Total Cost $ 4,860 4,100 3,320 5,880 $18, 160 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.

Required information [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. 2. Using FIFO, calculate ending inventory and cost of goods sold at October 31. Required information [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. 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 he October 10 purchase, and the October 28 sale consists of three purses from the October 10 purchase and four purses from the Dctober 20 purchase. Required information [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. 4. Using weighted-average cost, calculate ending inventory and cost of goods sold at October 31 . (Round your intermediate and final answers to 2 decimal places.) Required information [The following information applies to the questions displayed below] Sandra's Purse Boutique has the following transactions related to its top-selling Guccipurse for the month of October. Sandra's Purse Boutique uses a periodic inventory system. 3. Using LIFO, calculate ending inventory and cost of goods sold at October 31