Whirly Corporation's contribution format income statement for the most recent month is shown below: Sales (7,400 units) Variable expenses Contribution margin Fixed expenses Net operating income Total $ 229,400 140,600 88,800 55,700 $ 33,100 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 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 6,400 units? 1. Revised net operating income 2. Revised net operating income 3. Revised net operating income