Figure 6-4 price w D 10 20 30 40 50 60 70 80 quantity 30. Refer to Figure 6-4. Which of the following price controls would cause a surplus of 20 units of the good? a. a price floor of $8 b. a price ceiling of $5 c. a price ceiling of $4 d. a price floor of $7 31. Suppose the number of buyers in a market increases and a technological advancement occurs also. What would we expect to happen in the market? a. Equilibrium price would increase, but the impact on equilibrium quantity would be ambiguous. b. Equilibrium quantity would decrease, but the impact on equilibrium price would be ambiguous. c. Equilibrium price would decrease, but the impact on equilibrium quantity would be ambiguous. d. Equilibrium quantity would increase, but the impact on equilibrium price would be ambiguous