Last month when Holiday Creations, Inc., sold 36,000 units, total sales were $280,000, total variable expenses were $238,000, and fixed expenses were $36,400. Required: 1. What is the company's contribution margin (CM) ratio? 2. What is the estimated change in the company's net operating income if it can increase total sales by $1,800? (Do not round intermediate calculations.) 1. Contribution margin ratio 2. Estimated change in net operating income