Exercise 6-1 The Effect of Changes in Activity on Net Operating Income (L06-1] Whirly Corporation's contribution format income statement for the most recent month is shown below: Total Sales (8,600 units) Variable expenses Contribution margin Fixed expenses Net operating income Total $ 283,800 172,000 111,800 54,700 $ 57,100 Per Unit $ 33.00 20.00 $ 13.00 Required: (Consider each case independently): 1. What would be the revised net operating income per month if the sales volume increases by 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 7,600 units? 1. Revised net operating income 2. Revised net operating income 3. Revised net operating income