Engberg Company installs lawn sod in home yards. The company's most recent monthly contribution format income statement follows: Sales Variable expenses Contribution margin Fixed expenses Net operating income Required: Amount $ 123,000 Percent of Sales 49,200 73,800 100% 40 60% 22,000 $ 51,800 1. What is the company's degree of operating leverage? 2. Using the degree of operating leverage, estimate the impact on net operating income of a 13% increase in unit sales. 3. Construct a new contribution format income statement for the company assuming a 13% increase in unit sales.