Answer:
perfect competition; equal to $15
Explanation:
A Perfect competition industry is characterised by :
1. Firms that are price takers - They do not set price but prices are set by the forces of demand and supply.
2. Prices are equal to marginal revenue and average revenue.
3. plenty buyers and sellers.
4 free entry and exist of firms.
A monopolistic industry is chartcerised by :
1. Firms that are price makers.
2. Plenty buyers and sellers.
3. Price and average revenue are less than the marginal revenue
A monopoly is characterised by :
1. Firms that are price makers.
2. One seller
3. Price and average revenue are less than the marginal revenue