10) If a market begins in equilibrium and then the demand curve shifts leftward, a
A) shortage is created, which is eliminated by a fall in price.
B) shortage is created, which is eliminated by a rise in price.
C) surplus is created, which is eliminated by a fall in price.
D) surplus is created, which is eliminated by a rise in price.
點解唔係B

11) Which of the following is the best explanation why the price of gasoline
increases during the summer months?
A) Oil producers have lower costs of production in the summer.
B) Sellers have to earn profits during the summer to cover losses in the winter.
C) There is increased driving by families going on vacation.
D) There is less competition among oil refineries in the summer.