15. Muscat company has the following information for year 2020 Inventory on January 1, Year 2020 50 @ OMR 550 OMR 27,500 Inventories purchased during the year 50 @ OMR 600 30,000 Cost of Goods available for sale 100 units OMR 57,500 Note: 30 units are sold in Year 2020 Required: Calculate Cost of Goods Sold and Ending Inventory under LIFO, FIFO and Average cost methods