3. The XYZ Company has a contribution margin $50,000 and fixed expense $30,000. Sales are expected to increase by 50%. (1) Determine the percentage change in operating income. (2) Determine the expected amount of operating income. 4. At a price of $48, the estimated monthly sales of a product are 18,000 units. Variable expenses include manufacturing costs of $27 and distribution costs of $9. Fixed expenses are $60,000 per month. Determine the margin of safety in units