Exercise $2-4($Algo$)$ Computing and Using the CM Ratio $[$LO$2-3]$

Last month when Holiday Creations, Incorporated, sold $36,000$ units, total sales were $$144,000,$ total variable expenses were $$109,440,$ and fixed expenses were $$36,800.$

Required:

What is the company$$s contribution margin $($CM$)$ ratio?

What is the estimated change in the company$$s net operating income if it can increase sales volume by $475$ units and total sales by $$1,900?$

Note: Do not round intermediate calculations.