4. A company distributes a product that sells for $60 per unit. Variable expenses are $30 per unit and fixed expenses total $18,000 annually. Assume that the company sold 4,000 units last year. The manager is convinced that a 10% in the selling price, combined with a $30,000 increase in would net expenditures, w increase unit sales by 50%. If these changes were made, by how much operating income increase decrease? a. $17,700 increase b. $6,000 decrease c. $15,500 increase d. 000 decrease e. None of the above