PrepGo

AP Microeconomics Practice Quiz: The Effects of Government Intervention in Different Market Structures

Written by AP Content Team, Verified for 2026 AP Exams, Last updated: May 2026

Test your understanding with short quizzes. This quiz has 15 questions to check your progress.

Question 1 of 15

If the government imposes a lump-sum tax on a firm in an imperfectly competitive market, which of the following will occur in the short run?

All Questions (15)

If the government imposes a lump-sum tax on a firm in an imperfectly competitive market, which of the following will occur in the short run?

A) The firm's marginal cost curve will shift up.

B) The firm's output quantity will decrease.

C) The firm's fixed costs will increase.

D) The market price will increase.

Correct Answer: C

According to the provided content, lump-sum taxes do not change marginal cost or marginal benefit; only fixed costs will be affected. Therefore, the firm's fixed costs will increase, but its output and price decisions, which are based on marginal analysis, will not change in the short run.

When a per-unit tax is imposed on a good sold in a perfectly competitive market, the tax burden falls more heavily on consumers than producers under which condition?

A) When supply is more price elastic than demand.

B) When demand is more price elastic than supply.

C) When both demand and supply are perfectly inelastic.

D) When the tax is a lump-sum tax instead of a per-unit tax.

Correct Answer: A

The content states that the impact of a per-unit tax depends on the price elasticity of demand and supply. The burden of a tax falls more heavily on the side of the market that is less elastic (less responsive to price changes). Therefore, if consumers are to bear a larger portion of the tax, their demand must be less elastic than the producers' supply.

What is a primary goal of governments using price regulation, such as a price ceiling, on a monopoly?

A) To guarantee the monopolist earns a profit.

B) To increase the monopolist's producer surplus.

C) To address inefficiency and move the market outcome closer to the allocatively efficient quantity.

D) To increase the deadweight loss in the market.

Correct Answer: C

The provided content explicitly states that 'Government can use price regulation to address inefficiency due to monopoly.' By setting a price ceiling, the government can reduce the monopoly's market power, lower the price, and increase the quantity produced, thereby reducing deadweight loss and improving efficiency.

According to the provided text, what is the intended purpose of government antitrust policy?

A) To regulate natural monopolies to produce at the socially optimal level.

B) To provide lump-sum subsidies to firms incurring losses.

C) To correct for externalities by imposing per-unit taxes.

D) To make markets more competitive.

Correct Answer: D

The content clearly states, 'Governments use antitrust policy in an attempt to make markets more competitive.' This involves breaking up monopolies, preventing mergers that reduce competition, and prosecuting anti-competitive behavior.

A natural monopoly is regulated to produce at the allocatively efficient quantity, but at this quantity, it incurs an economic loss. Which government policy intervention would be necessary for the firm to continue operating in the long run?

A) A per-unit tax to cover the loss.

B) A binding price floor to raise the price.

C) A lump-sum subsidy to cover the fixed costs associated with the loss.

D) Antitrust action to break up the firm.

Correct Answer: C

The content specifies that 'A natural monopoly will require a lump-sum subsidy to produce at the allocatively efficient quantity.' This is because the allocatively efficient point (P=MC) is often below the firm's Average Total Cost, leading to a loss. A lump-sum subsidy can cover this loss without distorting the firm's marginal cost and output decision.

In a perfectly competitive market, what is the direct result of a binding price ceiling?

A) A surplus of the good, where quantity supplied exceeds quantity demanded.

B) An increase in both consumer and producer surplus.

C) A shortage of the good, where quantity demanded exceeds quantity supplied.

D) The market price and quantity moving to a new, higher equilibrium.

Correct Answer: C

The content explains that binding price ceilings affect prices and quantities. A binding price ceiling is set below the equilibrium price. At this lower price, consumers will demand a higher quantity, while producers will supply a lower quantity, resulting in a shortage.

Which of the following correctly distinguishes the effects of a per-unit subsidy from a lump-sum subsidy?

A) A per-unit subsidy affects marginal cost, while a lump-sum subsidy affects fixed cost.

B) A per-unit subsidy affects fixed cost, while a lump-sum subsidy affects marginal cost.

C) Both subsidies affect marginal cost, but only the per-unit subsidy creates deadweight loss.

D) Both subsidies affect fixed cost, but only the lump-sum subsidy increases output.

Correct Answer: A

The content differentiates between the two types of subsidies. Per-unit subsidies affect the marginal cost of production, encouraging firms to increase output. In contrast, lump-sum subsidies do not change marginal cost or marginal benefit; they only affect fixed costs, essentially acting as a grant to the firm.

Under what condition can government intervention in an imperfect market, such as a monopoly, lead to an increase in economic efficiency?

A) Only when the intervention benefits producers more than consumers.

B) Only when the intervention is in the form of a per-unit tax.

C) If the policy correctly addresses the incentives that led to the market failure.

D) If the policy guarantees that all firms in the market earn zero economic profit.

Correct Answer: C

This question directly tests the principle outlined in the content: 'Government intervention in imperfect markets can increase efficiency if the policy correctly addresses the incentives that led to the market failure.' For example, regulating a monopoly's price addresses the incentive to restrict output and charge a higher price.

Suppose the government imposes a $2 per-unit tax on sellers in a market. After the tax, the equilibrium quantity sold is 100 units. What is the total tax revenue collected by the government?

A) $50

B) $100

C) $200

D) Cannot be determined without knowing the equilibrium price.

Correct Answer: C

The content states that per-unit taxes affect government revenue. Government revenue from a per-unit tax is calculated by multiplying the tax amount per unit by the equilibrium quantity sold after the tax is imposed. In this case, the calculation is $2 (tax per unit) * 100 (units sold) = $200.

In a perfectly competitive market for agricultural products, the government imposes a binding price floor. Which of the following outcomes is most likely?

A) A decrease in producer surplus and an increase in consumer surplus.

B) A market shortage, as consumers demand more than is supplied.

C) A market surplus, as the quantity supplied exceeds the quantity demanded.

D) An increase in total economic surplus (consumer + producer surplus).

Correct Answer: C

The content notes that binding price floors affect prices and quantities. A binding price floor is set above the equilibrium price. This higher price incentivizes producers to supply more, but it discourages consumers from buying as much, leading to a surplus where quantity supplied is greater than quantity demanded.

Unlike in a perfectly competitive market, a binding price ceiling imposed on a single-price monopoly can sometimes have what effect?

A) Increase the deadweight loss.

B) Increase the quantity produced.

C) Shift the marginal cost curve upwards.

D) Create a surplus of the good.

Correct Answer: B

The content states that price ceilings affect quantities differently depending on the market structure. For a monopoly that restricts output to raise prices, a carefully placed price ceiling below the monopoly price can incentivize the firm to increase its output because it can no longer raise the price. This can move the quantity closer to the efficient level, thus increasing the quantity produced.

When the government provides a per-unit subsidy to the producers of a good, what is the resulting change in the market?

A) The price consumers pay increases, and the net price firms receive decreases.

B) The equilibrium quantity decreases, and a deadweight loss is created.

C) The price consumers pay decreases, and the net price firms receive increases.

D) Both consumer and producer surplus decrease.

Correct Answer: C

The content explains that per-unit subsidies affect the total price consumers pay and the net price firms receive. A subsidy effectively lowers the cost of production, shifting the supply curve to the right. This leads to a lower equilibrium price for consumers, a higher net price for producers (market price + subsidy), and an increase in the equilibrium quantity.

Which government policy will affect a firm's marginal cost curve?

A) A lump-sum tax.

B) A lump-sum subsidy.

C) A per-unit tax.

D) Antitrust litigation.

Correct Answer: C

Based on the provided content, per-unit taxes and subsidies directly impact the cost of producing one additional unit. Therefore, a per-unit tax increases marginal cost. In contrast, lump-sum taxes and subsidies only affect fixed costs and do not change marginal cost or marginal benefit.

In a monopsony market for labor, a binding minimum wage (a price floor) is imposed. How might this government intervention affect the market outcome?

A) It will definitely decrease employment and create a surplus of labor.

B) It can increase employment by moving the wage closer to the competitive equilibrium.

C) It will decrease the firm's marginal factor cost of labor.

D) It will have no effect because the monopsonist already sets the wage.

Correct Answer: B

The content states that price floors affect quantities differently depending on the market structure, including monopsony. A monopsonist hires fewer workers at a lower wage than a competitive market. A carefully set minimum wage can force the monopsonist to pay a higher wage, which can also increase the quantity of labor supplied and hired, moving employment closer to the efficient level.

A per-unit tax is placed on a product with perfectly inelastic demand and a typically sloped supply curve. What will be the effect on consumer surplus, producer surplus, and deadweight loss?

A) Consumer surplus decreases, producer surplus is unchanged, and there is no deadweight loss.

B) Consumer surplus is unchanged, producer surplus decreases, and there is a large deadweight loss.

C) Both surpluses decrease, and there is a large deadweight loss.

D) Consumer surplus decreases, producer surplus decreases, and there is no deadweight loss.

Correct Answer: A

The content notes that the impact of a tax depends on elasticity. With perfectly inelastic demand, consumers will buy the same quantity regardless of the price. Therefore, producers can pass the entire tax on to consumers. The price consumers pay rises by the full amount of the tax. Consumer surplus decreases by the amount of the tax revenue. Producer surplus is unchanged. Because the quantity does not change, there is no deadweight loss.