Required information (The following information applies to the questions displayed below.) Donaldson Company's contribution format income statement for the most recent month is shown below: Sales Variable expenses Contribution margin Fixed expenses Net operating income Total $500,000 300,000 200,000 180,000 $ 20,000 Per Unit $12.50 7.50 $ 5.00 The company sold 40,000 units in its most recent month and its relevant range of production is 30,000 to 50,000 units. Click here to download the Excel template, which you will use to answer the questions that follow. Click here for a brief tutorial on Goal Seek in Excel. Click here for a a brief tutorial on Charts in Excel. 2. Refer back to the Excel file. Using Goal Seek: a. Calculate the unit sales required to break even. b. Calculate the unit sales required to attain a target profit of $25,000. What would be the company's margin of safety at this level of sales? c. Calculate the unit sales required to attain a margin of safety of $75,000