Profit
Total revenue - total costs
Sales revenue
Quantity sold x selling price
Total costs
Fixed costs + variable costs
Break even
Fixed costs / (selling price per unit - variable costs per unit)
contribution
selling price - variable costs
margin of safety
selected level of business activity - break even output
% change
( difference / original ) x100
income elasticity of demand
% change in quantity / % change in income
price elasticity of demand
% change in quantity / % change in price