please do it correctly

Data for Hermann Corporation are shown below: Selling price Variable expenses Contribution margin Per Unit $ 65 39 $ 26 Percent of Sales 100% 60 40% Fixed expenses are $73,000 per month and the company is selling 4,300 units per month. Required: 1-a. How much will net operating income increase (decrease) per month if the monthly advertising budget increases by $9.700, the monthly sales volume increases by 100 units, and the total monthly sales increase by $6,500? 1-b. Should the advertising budget be increased