to be profitable, a firm has to recover its costs. these costs include both its fixed and its variable costs. one way that a firm evaluates at what stage it would recover the invested costs is to calculate how many units or how much in dollar sales is necessary for the firm to earn a profit. blue mouse manufacturers is considering a project that will have fixed costs of $15,000,000. the product will be sold for $37.50 per unit, and will incur a variable cost of $10.75 per unit. given the cost structure of blue mouse, it will have to sell units to break even on this project (qbeqbe).