d. The economies of some major oil-using nations, like Japan, slow down. e. A war in the Middle East disrupts oil-pumping schedules. f. Landlords install additional insulation in buildings. g. The price of solar energy falls dramatically. h. Chemical companies invent a new, popular kind of plastic made from oil. a. More fuel-efficient cars means there is less need for gasoline. This causes leftward shift in the demand for gasoline and thus oil. Since the demand c shifting down the supply curve, the equilibrium price and quantity both fal the