chegg during 2021, wmc corporation discovered that its ending inventories reported on its financial statements were misstated by the following amounts: 2019 understated by $ 120,000 2020 overstated by 150,000 wmc uses the periodic inventory system and the fifo cost method. required: 1-a. determine the effect of 2019 errors on retained earnings at january 1, 2021, before any adjustments. (ignore income taxes.) 1-b. determine the effect of 2020 errors on retained earnings at january 1, 2021, before any adjustments. (ignore income taxes.) 2. prepare a journal entry to correct the error in 2021. 3. will wmc account for the error (a) retrospectively or (b) prospectively?