The following monthly data are available for the Empire Company and its only product, Product DW: Total Per Unit Sales (400 units) $110,000 $275 Variable expenses 44,000 110 Contribution margin $66,000 $165 Fixed expenses 52,800 Net income $13,200 Required: a) Without resorting to calculations, what is the total contribution margin at the break-even point? b) Management is contemplating the use of plastic gearing rather than metal gearing in Product DW. This change would reduce variable costs by $15. The company's marketing manager predicts that this would reduce the overall quality of the product and thus would result in a decline in sales to a level of 350 units per month. Should this change be made? c) Assume that Empire Company is currently selling 400 units of Product DW per month. Management wants to increase sales and feels that this can be done by cutting the selling price by $25 per unit and increasing the advertising budget by $20,000 per month. Management believes that these actions will increase unit sales by 50%. Should these changes be made?