help explain please

Assuming the periodic inventory system, on November 30th there are 23 items left in inventory. Determine the Total Cost of the Goods Sold and the Total Cost of the Ending Inventory using a) FIFO b) LIFO c) Weighted Average, d) Specific Identification that show cost of goods sold consists of 7 units from Nov 1 inventory, 35 units from Nov 6 inventory, 30 units from the Nov 14 and 5 units from Nov 24 inventory