Competitive Markets and Externalities Price of Ice-Cream A tax on sellers shifts Price Cone Equilibrium Sz the supply curve buyers with tax upward by the size of pay S the tax ($0.50). $3.30 Tax ($0.50) Price 3.00 without 2.80 Equilibrium without tax tax Price sellers receive Demand, D. O 90 100 Quantity of Ice-Cream Cones