11 Porter Corporation has fixed costs of $660,000, variable costs of $24 per unit, and a contribution margin ratio of 40 percent. Compute the unit sales price and unit contribution margin for the above product. Porter Corporation has fixed costs of $660,000, variable costs of $24 per unit, and a contribution margin ratio of 40 percent. Compute the dollar sales volume required for Porter Corporation to earn an operating income of $300,000