5 Feather Friends, Inc, distributes a high quality wooden birdhouse that sells for $40 per unit. Variable expenses are $20.00 per unit, and fixed expenses total $180,000 per year. Its operating results for last year were as follows: 10 points Sales Variable expenses Contribution margin Fixed expenses Net operating Income $ 1,120,000 560,000 560.000 180,000 $ 380,000 eBook Print References Required: Answer each question independently based on the original data: 6. The president does not want to change the selling price. Instead, he wants to increase the sales commission by $180 per unit. He thinks that this move, combined with some increase in advertising, would increase this year's unit sales by 25% How much could the president increase this year's advertising expense and still earn the same $380.000 net operating income as last year