Fill in the missing amounts in each of the eight case situations below. Each case is independent of the others. (Hint: One way to find the missing amounts would be to prepare a contribution format income statement for each case, enter the known data, and then compute the missing items.) Required: a. Assume that only one product is being sold in each of the following four case situations: Unit sold Sales Vanable expenses Fixed expenses Operating income (loss) Contribution margin per unit Case #1 Case #2 Case #3 Case #4 19,200 12,000 7,680 $ 230,400 $ 128,000 $ 384,000 153,600 89,600 64,000 40,960 128,000 $ 10,240 $ 15,360 $ (12,800) $ 10 $ 13 b. Assume that more than one product is being sold in each of the following four case situations: (Enter "Contribution margin ratio in percent. Round your final answers to the nearest whole dollar amount.) Case #1 Case #2 Case #3 Case #4 Sales $ 528,000 $ 428,000 $ 678.000 Variable expenses 278.200 430,600 Fixed expenses 107,000 138,400 Operating income (loss) $ 8,400 $ 28.400 $ (4,000) Average contribution margin (percentage) 20% 60%