The following monthly data are available for the Choice Company and its Required: a) Calculate the company's break-even point in units and sales $ b) Calculate the company's contribution margin ratio c) Calculate the company's margin of safety in sales $ d) Management is contemplating the use of plastic gearing rather than metal gearing in Product SW. This change would reduce variable costs by $15 per unit. 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