6 Sparkle is one of the many firms in the market for toothpaste, which is in long-run equilibrium.

a Draw a diagram showing Sparkle's demand curve, marginal-revenue curve, averagetotal-cost curve and marginal-cost curve. Label Sparkle's profit-maximising output and price.

b What is Sparkle's profit? Explain.

c On your diagram, show the consumer surplus derived from the purchase of Sparkle toothpaste. Also show the deadweight loss relative to the efficient level of output.

d If the government forced Sparkle to produce the efficient level of output, what would happen to the firm? What wou ld happen to Sparkle's customers?