Martinez Company began operations on January 1, 2018, and uses the average-cost method of pricing inventory. Management is contemplating a change in inventory methods for 2021. The following information is available for the years 2018-2020. 2018 2019 2020 Net Income Computed Using Average-Cost Method FIFO Method LIFO Method $15,860 $18,810 $12,090 18,010 20,800 14.140 19,970 24.990 16,870 (a) Prepare the journal entry necessary to record a change from the average cost method to the FIFO method in 2021. (Credit account titles are automatically indented when amount is entered. Do not indent manually. If no entry is required, select "No Entry" for the account titles and enter O for the amounts.) Account Titles and Explanation Debit Credit (b) Determine net income to be reported for 2018, 2019, and 2020, after giving effect to the change in accounting principle. Net Income 2018 $ 2019 $ 2020 $