yugan operations on July 1, 2015, and has used the average-cost method of inventory valuation since its inception. In 2019, it decides to switch to the FIFO method. You are provided with the following information: Retained Earnings (Ending Balance) Net Income Under Average-Cost Under FIFO Under Average Cost 2015 $52,000. $57,000 $57,000 2016 126,000 136,000 173,000 2017 159,000 184,000 319.000 2018 115,000 120,000 398,000 (a) What is the beginning retained earnings balance at January 1, 2016, if Sheridan prepares comparative financial statements starting in 2018? Retained earnings, January 1 67000