What was the degree of operating leverage in 2013?

Stanley appliances producewashing machines and dryers. The company’s external income statements for the last two years are given below:2012 2013 2014?Units Sold 150,000 195,000Sales Revenue$ 2,160,000$ 2,700,000Cost of Goods Sold 1,358,000 1,718,000Gross Margin 802,000982,000
S, G & A 210,000 210,000Net Operating Income $ 592,000 $ 772,000The company has no beginning or ending inventories. Manufacturing costs are mixed, while S,G&A costs are strictly fixed.Required:1. Use the “high-low” method to estimate the variable manufacturing cost per unit and the total fixed manufacturing cost.Variable Mfg. cost per unit =Total Fixed Mfg. costs =2. How much total contribution margin was earned in 2012 year?3. What was the degree of operating leverage in 2013?4. If sales increase by 15% from 2013 to 2014, how much net operating income will the company earn in 2014?5. Assume that total assets decreased from $14,000,000 to $10,000,000 during 2013. The company’s minimum acceptable rate of return is 6%. Compute the following for 2013:Return on Sales =Investment Turnover =Return on Investment =Residual Income =