Data Concerning Lemelin Corporation's Single Product Appear Below

Data concerning Lemelin Corporation's single product appear below:
The company is currently selling 7,000 units per month. Fixed expenses are $581,000 per month. Consider each of the following questions independently.
-This question is to be considered independently of all other questions relating to Lemelin Corporation.Refer to the original data when answering this question. The marketing manager would like to introduce sales commissions as an incentive for the sales staff.The marketing manager has proposed a commission of $20 per unit.In exchange,the sales staff would accept a decrease in their salaries of $113,000 per month.(This is the company's savings for the entire sales staff.) The marketing manager predicts that introducing this sales incentive would increase monthly sales by 300 units.What should be the overall effect on the company's monthly net operating income of this change?

A) decrease of $224,500
B) increase of $107,000
C) increase of $1,500
D) increase of $806,500