The following monthly budgeted data are available for the Stark Company Product A Product B Product C Sales $500,000 $300,000 $900,000 Variable expenses 300,000 210,000 720,000 Contribution margin $200,000 $90,000 $180,000 Budgeted operating income for the month is $220,000, Submission instructions: a) Calculate the break-even sales for the month. b) Calculate the margin of safety c) Calculate the degree of operating leverage