Lusk Company produces and sells 15,000 units of Product A each month. The selling price of Product A is $20 per unit, and variable expenses are $14 per unit. A study has been made concerning whether Product A should be discontinued. The study shows that $70,000 of the $100,000 in fixed expenses charged to Product A would continue even if the product was discontinued. These data indicate that if Product A is discontinued, the company's overall net operating income would: A) decrease by $60,000 per month B) increase by $10,000 per month C) increase by $20,000 per month D) decrease by $20,000 per month

i know the answer is 60k but could someone explain the process to get the answer