Whirly Corporation's contribution format income statement for the most recent month is shown below Sales (9,000 units) Variable expenses Contribution margin Fixed expenses Net operating income Total $ 279,000 162,000 117,000 55,100 $ 61,900 Per Unit $ 31.00 18.00 $ 13.00 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 8,000 units? 1. Revised not operating income 2. Revised net operating income 3 Revised net operating income