12. Mach Corporation is a wholesaler that sells a single product. Management has provided the following cost data for two levels of monthly sales volume. The company sells the product for $104.50 per unit. Sales volume (units) 5,000 6,000 Cost of sales $ 295,000 $ 354,000 Selling and administrative costs $ 186,000 $ 202,800 Net Income The best estimate of the total monthly fixed cost is: a. $102,000 b. $518,900 c. $556,800 d. $481,000