Panel (a) Panel (b) Four graphs of price versus quantity illustrate relationships between supply and demand. A graph of price, P, versus quantity, Q, shows a single supply curve, S, and two parallel demand curves, D and D prime. The supply curve ascends to the right, whereas the demand curves descend to the right. D is the left curve, and D prime is the right. Curves S and D intersect at point (Q sub e, P sub e), and curves S and D prime intersect at point (Q sub e prime, P sub e prime). A right arrow indicates a change in demand from D to D prime resulting in an increase in the market demand from Q sub e to Q sub e prime, and an up arrow indicates a corresponding increase in the price from P sub e to P sub e prime. A graph of price, P, versus quantity, Q, shows a single supply curve, S, and two parallel demand curves, D and D prime. The supply curve ascends to the right, whereas the demand curves descend to the right. D prime is the left curve, and D is the right. Curves S and D intersect