Iadanza Corporation is a wholesaler that sells a singler product. Management has provided the following cost data for two levels of monthly sales volume. The company sells the product for $195.70 per unit.

Sales Volume...................................6,000 7,000

Cost of Sales.....................................$457,800 $534,100

Selling & Administrative costs............$621,000 $639,100

The best estimate of the total contribution margin when 6,300 units are sold is:

A. $752,220

B. $638,190

C. $100,170

D. $177,030

Please show the steps to the answer.