Whirly Corporation's contribution format income statement for the most recent month is shown below: Sales (7,800 units) Variable expenses Contribution margin Fixed expenses Net operating income Total $ 249,600 156,000 93,600 54,000 $ 39,600 Per Unit $ 32.00 20.00 $12.00 Required: (Consider each case independently): 1. What would be the revised net operating income per month if the sales volume increases by 40 units? 2. What would be the revised net operating income per month if the sales volume decreases by 40 units? 3. What would be the revised net operating income per month if the sales volume is 6,800 units? 1. Revised net operating income Revised net operating income 3. Revised net operating income