Whirly Corporation's contribution format income statement for the most recent month is shown below: Sales (8,900 units) Variable expenses Contribution margin Fixed expenses Net operating income Total $ 275,900 169, 100 106,800 55,300 $ 51,500 Per Unit $ 31.00 19.00 $ 12.00 Required: (Consider each case independently): 1. What would be the revised net operating income per month if the sales volume increases by 60 units? 2. What would be the revised net operating income per month if the sales volume decreases by 60 units? 3. What would be the revised net operating income per month if the sales volume is 7,900 units? 1. Revised net operating income 2. Revised net operating income 3. Revised net operating income