Hello, I need help with this Managerial Accounting problem.

Last month when Holiday Creations, Inc., sold 36,000 units, total sales were $308,000, total variable expenses were $215,600, and fixed expenses were $38,800. 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.) 2 Contribution margin ratio Estimated change in net operating income