Fixed expenses are $78,000 per month and the company is selling 3,500 units per month. xercise 5-5 (Algo) Part 1 Required: 1-a. How much will net operating income increase (decrease) per month if the monthly advertising budget increases by $8,300, monthly sales volume increases by 100 units, and the total monthly sales increase by $9,000 ? 1.b. Should the advertising budget be increased? Complete this question by entering your answers in the tabs below