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 Variable expenses Fixed expenses Operating income (loss) Contribution margin per unit Case #1 Case #2 Case #3 Case #4 19,500 13,000 7,800 $ 234,000 $ 130,000 $ 390,000 156,000 91,000 65,000 41,600 130,000 $ $ 10,400 $ 10 $ 15,600 $ 13 (13,000) 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 $ 530,000 $ 430,000 $ Variable expenses 279,500 630,000 441,000 Fixed expenses 107,500 139,000 Operating income (loss) $ 8,500 $ 29,000 $ (5,000) Average contribution margin (percentage) 20% 60%