For each of the six independent situations below, compute the missing amounts. a. Using contribution margin per unit: (Omit the "$" sign in your response) Sales Variable Costs Contribution Margin per Unit Fixed Costs Operating Income Units Sold (1) $ $ 120,000 $ 20 $ $ 25,000 4,000 (2) 180,000 45,000 30,000 5,000 (3) 600,000 30 150,000 90,000 b. Using the contribution margin ratio: (Omit the "$" and "%" signs in your response) Sales Variable Costs Contribution Margin Ratio (%) Fixed Costs Operating Income (1) $ 900,000 $ 720,000 % $ $ 95,000 (2) 600,000 40 % 75,000 (3) 30 % 90,000 60,000