Engberg Company installs lawn sod in home yards. The company's most recent monthly contribution format income statement follows: Percent of Amount Sales Sales Variable expenses Contribution margin $ 139,000 100% 55,600 40% 83,400 60% ok Fixed expenses 21,000 Net operating income $ 62,400 nt ht nces Required: 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 14% increase in sales. 3. Construct a new contribution format income statement for the company assuming a 14% increase in sales.