From Wikipedia, the free encyclopedia. Phototoxicity, also called photoirritation, is a chemically induced skin irritation, requiring light, that does not involve the immune system. It is a type of photosensitivity. The skin response resembles an exaggerated sunburn.
The contribution margin ratio is the difference between a company's sales and variable expenses, expressed as a percentage. The total margin generated by an entity represents the total earnings available to pay for fixed expenses and generate a profit.
Cost-volume-profit analysis is used to determine the profit-maximizing level of output. The contribution margin per unit is equal to price minus short-run average variable cost. Breakeven output is equal to total fixed cost divided by the contribution margin per unit.ost-volume-profit analysis is used to determine the profit-maximizing level of output. The contribution margin per unit is equal to price minus short-run average variable cost. Breakeven output is equal to total fixed cost divided by the contribution margin per unit.