If the equilibrium quantity is 15 and the equilibrium price is 20, and the maximum someone is willing to pay is 40 and the supply curve intersects the y axis at zero:

A. Draw the graph of supply and demand using the information above

B. Calculate the consumer surplus using the formula for the area of a triangle: Base x Height

C. Calculate the producer surplus using the formula for the area of a triangle: Base x Heigh

D. What is the total surplus?

E. If this market is perfect competition, is it efficient?