Required information [The following information applies to the questions displayed below.] Data for Hermann Corporation are shown below: Fixed expenses are $87,000 per month and the company is selling 2,900 units per month. Required: a. How much will net operating income increase (decrease) per month if the monthly advertising budget increases by $9,200, the nonthly sales volume increases by 100 units, and the total monthly sales increase by $13,500 ? b. Should the advertising budget be increased? How much will net operating income increase (decrease) per month if the monthly advertising budget Increases by $9,200, the monthly sales volume increases by 100 units, and the total monthly sales increase by $13,500 ? (Do not round intermediate calculations.) Should the advertising budget be increased