perpetual inventory using FIFO. please give an explanation on how to receive the values necessary to fill chart

Dec. 1220 units at $29 Sales Dec. 12154 units 14132 units 3166 units cost column. FIFO Method Prepaid Cell Phones Cost of Cost of Cost of Purchases Purchases Purchases Goods Sold Goods Sold Goods Sold Inventory Inventory Inventory Date Quantity Unit Cost Total Cost Quantity Unit Cost Total Cost Quantity Unit Cost Total Cost Dec. 1 Dec. 10 . Dec. 20