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 (10,000 units) Variable expenses Contribution margin Fixed expenses Net operating income Total $ 350,000 200,000 150,000 135,000 $ 15,000 Per Unit $35.00 20.00 $15.00 Required: (Consider each case independently): 1. What would be the revised net operating income per month if the sales volume increases by 100 units? 2. What would be the revised net operating income per month if the sales volume decreases by 100 units? 3. What would be the revised net operating income per month if the sales volume is 9,000 units? 1. Revised net operating income Revised net operating income Revised net operating income 3. Exercise 5-4 Computing and Using the CM Ratio (LO5-3] Last month when Holiday Creations, Inc., sold 50,000 units, total sales were $200,000, total variable expenses were $120,000, and fixed expenses were $65,000. Required: 1. What is the company's contribution margin (CM) ratio? 2. What is the estimated change in the company's net operating income if it can increase total sales by $1,000? 1. Contribution margin ratio 2. Estimated change in net operating income