Exercise 5-1 The Effect of Changes in Activity on Net Operating Income [LO5-1 Whirly Corporation's contribution format income statement for the most recent month is shown below Sales (7,200 units) Variable expenses Contribution margin Fixed expenses Net operating income s 230,400 144,000 32.00 20.00 86,400 12.00 54,600 s 31,800 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 6,200 units? net net operating income 3. Revised net operating income