Suring 2021. WMC Corporation discovered that its ending inventories reported on its financial statements were misstated by the oliowing amounts: WMC uses the periodic inventory system and the FIFO cost method. Required: 1-. Determine the effect of 2019 errors on retained earnings at January 1, 2021, before any adjustments. (lgnore income taxes.) 1-b. Determine the effect of 2020 errors on retained eamings at January 1. 2021, before any adjustments. (lgnore income taxes.) 2. Prepare a journal entry to correct the error in 2021 3. Wii WMC account for the error (a) retrospectively or (b) prospectively? Complete this question ty entering your answers in the tabs below. Detertnifie the effect of 2019 errors on retained earnings at january 1, 2021, before any adjustments. (tgnore incorne taxes.) (14 the answem is no niftect then select "No effect in the dropdown.)