Last month when Holiday Creations, Incorporated, sold $42,000$ units, total sales were $$168,000,$ total varlable expenses were

$$122,640,$ and fixed expenses were $$38,700.$

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 $400$ units and total sales by

$$1,600?($Do not round Intermedlate calculations.$)$