28) Suppose we observe that both the equilibrium price of digital cameras and the equilibrium
quantity of digital cameras have increased. Which of the following events could be responsible
for this?
A) technological advances in digital camera production
B) consumers’ preferences changed in favor of digital cameras
C) the price of film cameras fell
D) workers who make digital cameras received a pay raise
29) Suppose we observe that both the equilibrium price of film cameras and the equilibrium
quantity of film cameras have fallen. Which of the following could be responsible for this?
A) Consumers’ preferences changed in favor of digital cameras.
B) technological advances in film camera production
C) Workers who make cameras received a pay raise.
D) The price of digital cameras increased.
30) During the past twenty years, the prices of prescription drugs, relative to the prices of other
goods, have risen, yet Americans buy more prescription drugs than ever. This might be because
A) with higher incomes and more older Americans, we have moved rightward along our demand
curve for drugs.
B) with higher incomes and more older Americans, the demand curve for prescription drugs has
shifted rightward.
C) more new firms entered the pharmaceutical industry each year, which caused a rightward shift
in the supply curve of prescription drugs.
D) Both answers A and C are correct.
31) You observe that in the market for coffee that both the equilibrium price of coffee and the
equilibrium quantity have increased. You predict that the demand for coffee
A) has increased with no change in the supply of coffee.
B) has increased but it is not as large as the increase in supply.
C) has not changed but that the supply of coffee has decreased.
D) has increased less than supply of coffee has decreased.