Depict on a graph a perfectly competitive market with a negative externality. Utilise the graph to cleary highlight and discuss the problems associated with the negative externality.[hint: focus on the quantity difference between the market equilibrium and the socially desirable equilibrum] now consider what happens if the market consolidates and becomes a monopoly (there is no need to depict this on a graph). Do you think the obesity and diabetes will increase or decrease? [hint: focus on the quantity difference betweeen a monopoly and perfectly competitive market]