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.
Contribution margin ratio measures the percentage of sales that would increase net income. To calculate it, divide contribution margin by sales, either in total or per unit: Suppose a gadget selling for $100 per unit brings in $40 per unit of contribution margin.
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.