Data for Hermann Corporation are shown below: Per Unit Percent of Sales Selling price $ 130 100 % Variable expenses 78 60 Contribution margin $ 52 40 % Fixed expenses are $86,000 per month and the company is selling 2,800 units per month. Required: 1-a. How much will net operating income increase (decrease) per month if the monthly advertising budget increases by $9,100 and monthly sales increase by $19,500