Whirley Corporations contribution format income statement for the most recent month is shown below: Total Per Unit Sales (8,600 units) $ 275,200 $ 32.00 Variable expenses 154,800 18.00 Contribution margin 120,400 $ 14.00 Fixed expenses 55,600 Net operating income $ 64,800 Required: (Consider each case independently): 1. What would be the revised net operating income per month if the sales volume increases by 90 units? 2. What would be the revised net operating income per month if the sales volume decreases by 90 units? 3. What would be the revised net operating income per month if the sales volume is 7,600 units?