Consider three firms, A, B and C, all producing kilos of potatoes (per year) in a perfectly competitive market. The diagrams below show marginal cost curves for each of the three firms. Cost ($) Firm A Cost ($) Firm B Cost ($) Firm C Quantity MCC MCA MCB ........ A ON N 200 500 700 500 800 900 200 500 800 Quantity of potatoes Quantity of potatoes Quantity of potatoes