The Waldo Company had the following data for 2011: Sales ($20 x 20,000 units) $400,000 Variable cost $240,000 Fixed cost $100,000 Operating income $60,000 Required: A. Calculate the contribution margin per unit. B. What is the break-even point in units? C. What is the amount of sales in units needed to obtain an operating income of $40,000? D. What is the margin of safety in units, assuming operating income is $80,000