a.Prepare income statements under LIFO for 2015, 2016, and 2017.
b. Prepare income statements under FIFO for 2015, 2016, and 2017.
c. Prepare income statements reflecting the retrospective application of the accounting change from the LIFO method to the FIFO method for 2017 and 2016.
d. Prepare comparative retained earnings statements for 2016 and 2017 under FIFO.