Irene Company began operations on Jan 1, 2018 and uses the average cost method (AC) in costing its inventory. Irene is contemplating a change to the FIFO method. Accordingly, the following information has been developed: Ending Inventory AC 2018 $450 480 2019 $765 810 FIFO Condensed I/S for Irene, prepared under AC inventory method, for 2018 and 2019 appear below: Sales CGS GP SG&A NI Required: 2018 $3,000 1,800 $1,200 750 $ 450 Calculate CGS for each year under FIFO (8 marks) 2019 $3,600 2,160 $1,440 825 $ 615 Prepare the condensed I/S for Irene under FIFO for 2018 and 2019 (4 marks) Explain the difference between the 2018 NI's under AC and FIFO (2 marks), and the difference between the 2019 NI's under AC and FIFO (4 marks)