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Concord Company started operations on January 1, 2015, and has used the FIFO method of inventory valuation since its inception In 2021, it decides to switch to the average-cost method. You are provided with the following information. Retained Earnings (Ending Balance) Under FIFO $101,800 172,800 257,100 2015 Net Income Under FIFO Under Average-Cost $109,300 $99,300 73,600 69,000 86,500 76,400 119,500 129,900 299,300 289,800 302,300 307,300 2016 2017 2018 2019 2020 307,400 625,300 745,600 (a) What is the beginning retained earnings balance at January 1, 2017, if Concord prepares comparative financial statements starting in 2017? Retained earnings, January 1 $ (b) What is the beginning retained earnings balance at January 1, 2020, if Concord prepares comparative financial statements starting in 2020? Retained earnings, January 1 $ (c) What is the beginning retained earnings balance at January 1, 2021, if Concord prepares single-period financial statements for 20212 Retained earnings, January 1 $ (d) What is the net income reported by Concord in the 2020 income statement if it prepares comparative financial statements starting with 2018? 2018 2019 2020 Net Income $ $