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Last perlod Hartig Corporation sold 36,000 units, total sales were $312,000, total variable expenses were $240,240, and fixed expenses were $35,100 Required: 1. What is the company's contribution margin (CM) ratlo? 2. What is the estimated change in the company's net operating income if it can increase total sales by $2,600? (Do not round Intermediate calculations.) 1. Contribution margin ratio 2. Estimated change in net operating income