Data for Hermann Corporation are shown below: Selling price Variable expenses Contribution margin Per Unit $ 85 51 $ 34 Percent of Sales 1003 60 400 Fixed expenses are $77,000 per month and the company is selling 2,600 units per month. Required: 1-a. How much will net operating income increase (decrease) per month if the monthly advertising budget increases by $8,200, the monthly sales volume increases by 100 units, and the total monthly sales increase by $8,500? 1-b. Should the advertising budget be increased