Engberg Company installs lawn sod in home yards. The company's most recent monthly contribution format income statement follows: Percent o Sales 1008 408 608 Amount Sales Variable expenses Contribution margin Fixed expenses Net operating income 140,000 56,000 84,000 16,000 $ 68,000 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 20% increase in sales. 3. Construct a new contribution format income statement for the company assuming a 20% increase in sales