Novak co. decides at the beginning of 2017 to adopt the fifo method of inventory valuation. novak had used the lifo method for financial reporting since its inception on january 1, 2015, and had maintained records adequate to apply the fifo method retrospectively. novak concluded that fifo is the preferable inventory method because it reflects the current cost of inventory on the balance sheet. the following table presents the effects of the change in accounting principles on inventory and cost of goods sold. inventory determined by cost of goods sold determined bydatelifo methodfifo methodlifo methodfifo methodjanuary 1, 2015 $ 0 $ 0 $ 0 $ 0december 31, 2015 110 9 750 851december 31, 2016 200 260 940 779december 31, 2017 320 400 1,150 1,130retained earnings reported under lifo are as follows. retained earnings balancedecember 31, 2015 $1,090 december 31, 2016 1,990 december 31, 2017 2,680 other information: 1. for each year presented, sales are $2,770 and operating expenses are $930.2. novak provides two years of financial statements. earnings per share information is not required. 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.