ECON8069-Introduction to Economics Study Notes & Practice | The Australian National University | AskSia

Mar 12, 2026

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Top Professional @ Learning Made Easy: Economics Review Material Summary

This document contains exclusive review materials from "Top Professional" for internal students, covering key microeconomics concepts and their applications, including market structures, consumer behavior, and government intervention.

I. Core Microeconomic Concepts

Taxation:
- Who Pays Tax: Examines the incidence of taxes, determining how the burden is shared between consumers and producers.
- Impact of Taxes: Analyzes how taxes affect market prices, quantities, consumer surplus, producer surplus, and government revenue. The relationship between tax impact and elasticity is crucial.
- Tax Revenue & Deadweight Loss: Discusses the calculation of government revenue and deadweight loss, noting that deadweight loss is positively related to the size of the tax and elasticity.
Price Controls:
- Price Floor:
  - Definition: A minimum price set above the market clearing price.
  - Impact: Leads to a surplus of the good.
- Price Ceiling: (Mentioned in the context of Monopoly analysis)
- Subsidies: Analyzes their impact on consumer surplus, producer surplus, and total surplus.
- General Impact: Examines the effects of price controls on surplus.
Consumer Behavior:
- Utility Maximization: Consumers aim to maximize utility by equating the marginal benefit per dollar spent across goods: $MB_x / P_x = MB_y / P_y$.
- Budget Constraints: Consumers have limited budgets (e.g., Jenny's $50).
Demand and Supply:
- Demand Curve Shifts: Caused by factors other than the price of the good itself, such as changes in consumer wealth, the price of related goods (substitutes/complements), or consumer preferences (e.g., health announcements).
- Supply Curve Shifts: Caused by changes in input prices (e.g., cost of cocoa beans), technology, or the number of firms in the market. A decrease in marginal cost shifts the supply curve to the right.
- Movement Along vs. Shift: A change in the price of the good itself causes a movement along the curve, while other factors cause the entire curve to shift.
Elasticity:
- Price Elasticity of Demand: Measures the responsiveness of quantity demanded to a change in price. More elastic demand means consumers react more strongly to price changes.
- Cross-Price Elasticity: Measures the responsiveness of the demand for one good to a change in the price of another good.
  - Substitutes: Positive cross-price elasticity (e.g., sausages and hamburgers).
  - Complements: Negative cross-price elasticity.
- Relationship with Tax: Greater elasticity of demand leads to smaller tax revenue and larger deadweight loss. Conversely, less elastic demand leads to higher tax revenue and smaller deadweight loss.
Market Structures:
- Perfect Competition:
  - Characteristics: Many identical firms, price takers.
  - Short-Run: Firms can earn positive, negative, or zero economic profit.
  - Long-Run: Firms earn zero economic profit as new firms enter or exit the market.
- Monopoly:
  - Characteristics: Single seller, significant market power, barriers to entry (e.g., patents, high start-up costs).
  - Market Power: Ability to set price above marginal cost.
  - Profit Maximization: Produce where $MC = MR$. Calculating Marginal Revenue (MR) is crucial, often requiring calculation of Total Revenue (TR) first.
  - Natural Monopoly: Characterized by decreasing Average Total Cost (ATC) over the relevant range of output, making it most efficient for one firm to serve the market.
  - Impact: Leads to deadweight loss (DWL) compared to competitive markets. Analysis with price ceilings is a complex topic.
Costs and Production:
- Economic Scale (Economies of Scale): Refers to the relationship between input and output.
  - Increasing Returns to Scale: Average Total Cost (ATC) decreases as output increases.
  - Decreasing Returns to Scale: ATC increases as output increases.
  - Constant Returns to Scale: ATC remains constant.
- Opportunity Cost: Must always be considered in economic decision-making.
Surpluses:
- Consumer Surplus (CS): The difference between what consumers are willing to pay and what they actually pay. Represented by the area below the demand curve and above the price.
- Producer Surplus (PS): The difference between the price producers receive and their minimum willingness to sell. Represented by the area above the supply curve and below the price.
- Total Surplus (TS): The sum of Consumer Surplus and Producer Surplus ($TS = CS + PS$). Represents the total welfare in the market.
- Calculation: Typically calculated as the area of a triangle on a supply and demand graph.

II. Exam Strategy and Tips

Question Weighting: Multiple-choice questions are increasing in weight (around 45-50 points) and difficulty, making them essential for a good score.
Short Answer Questions: Decreasing in number and weight, but still important for differentiating performance. Difficulty remains similar.
Answering Strategy:
- Always define key terms in short answer questions.
- Use graphs whenever possible, ensuring all labels and points are clearly marked.
- Use symbols (like arrows) to indicate increases/decreases and logical connections (e.g., "because," "therefore").
- Logical correctness and completeness are key to scoring.

III. Examples and Applications

Tax on Bread: A per-unit tax on bread increases the price consumers pay and decreases the price suppliers receive.
Binding Price Floor: Results in a price above the market clearing price and creates a surplus.
Consumer Choice: Jenny's decision on buying beans and shoes based on her budget and prices. Sam's decision on apples and biscuits based on marginal benefits and prices.
Demand Shift Example: News that hot chocolate cures acne increases demand, shifting the curve right, leading to higher equilibrium price and quantity.
Supply Shift Example: A decrease in the marginal cost of producing calculators shifts the supply curve to the right.
Ice Cream Market Example:
- Restricting the number of ice cream shops shifts the industry supply curve left, increasing price and profit for remaining firms.
- Licence fees act as a lump-sum tax, reducing profits but not affecting output decisions ($MC=MR$). The optimal fee for the council is the economic profit of the firms.
Car Tax Example (Victoria): Decreasing a per-unit tax on cars increases quantity sold, decreases consumer price, and increases producer price. This also decreases deadweight loss. The impact on government revenue depends on the elasticity of demand; with elastic demand, a tax reduction is more likely to increase government revenue.
Monopoly Production: A monopoly firm with constant marginal cost of $4 will produce where $MR=MC$. If MR is calculated correctly from TR, this leads to a specific output level.
Hot Chocolate Market Scenarios:
- Substitute Price Fall (Coffee): Decreases demand for hot chocolate (leftward shift), lowering equilibrium price and quantity.
- Input Price Rise (Cocoa Beans): Decreases supply of hot chocolate (leftward shift), raising equilibrium price and lowering quantity.
- Positive Health News: Increases demand for hot chocolate (rightward shift), raising equilibrium price and quantity.

Disclaimer: This material is for internal study use only. Unauthorized distribution is prohibited.

请列出所有的题目

根据文档 8069期中押题.pdf，总结并列出出现的所有题目如下：

选择题（Multiple Choice Questions）与知识点题干

如果你需要上述每道题的详细内容或解析，请告诉我题号！
若需“简答模板”或解题技巧，也可进一步提供。

这些题目中哪些属于常见的考试题型？

以下是出现在 8069期中押题.pdf 中，并且属于“常见考试题型”的题目类型总结：

1. 多项选择题（Multiple Choice Questions — MCQ）

2. 简答题（Short Answer/Structured Questions）

3. 计算题（Quantitative Problems/Calculation Questions）

4. 图形题（Diagram/Graphical Questions）

归纳总结

这些题型都是经济学考试中最为常见和基础的考查方式。如果你掌握了这些类型的解题套路和作图技巧，就可以应对大部分经济学微观基础课程的期中&期末考试。
如需针对某种题型的答题模板或高分技巧，欢迎随时提问！

小提示：如果希望我为你记忆常考题型清单或解题模板，请告知，我可以下次自动为你调用。

做出解析

以下是“8069期中押题.pdf”中常见考试题型的题目解析示例：

1. 完全竞争市场和垄断（Monopoly）的区别

考点定位： 市场结构基本原理，考查分类能力与关键特征记忆 [4]Source: 8069期中押题.pdf次级知识点推荐: 1. 完全竞争市场和 Monopoly(垄断)的区别 2. 关于弹性的计算 3. 记住考虑 Opportunity Cost 考试趋向分析: 1. 选择题的比重上升,接近45~50分,难度加大,保分必备 2. 简答题比重减少,题量减少3小题左右,实际难度和上学期持平,拉开差距 Top Professional Top Professional 独家复习资料,仅限内部学员学习使用,盗版必究 @ Learning Made Easy

答题模板 & 解析：

定义/列举：完全竞争市场有大量买卖者、产品同质、无进入壁垒，每个厂商为“价格接受者”；垄断市场有唯一厂商，产品无替代，存在高进入壁垒（如专利），厂商可以控制价格。
核心区分：完全竞争行业长期利润为零，垄断则可能长期获利。
图形：常考P=MC和MC=MR对比。

2. 弹性计算与判断

考点定位： 供求的价格弹性和交叉价格弹性判定 [2]Source: 8069期中押题.pdf可以用见箭头符号表示增减、因为所以等;4,得分的关键在于是否逻辑正确,没有遗漏 Top Professional Top Professional 独家复习资料,仅限内部学员学习使用,盗版必究 @ Learning Made Easy Top Professional @ Learning Made Easy Top Professional 独家复习资料,仅限内部学员学习使用,盗版必究 7. From the information in figure 1 below we can see that: a. Consumer Surplus is $24, Producer Surplus is $9 and Total Surplus is $33. b. Consumer Surplus is $9, Producer Surplus is $24 and Total Surplus is $33. c. Consumer Surplus is $21, Producer Surplus is $12 and Total Surplus is $33.[6]Source: 8069期中押题.pdf7. Tax 的影响和弹性的关系,同时结合 Surplus、Tax revenue 的面积 8. 价格弹性(考察了互为替代品的交叉价格弹性的判定) 9. Economic Scale 的定义 10. 在完全竞争市场下,Firms 的 Short-term 和 Long-term 的情况 11. Monopoly 的特点,market power,自然垄断的定义 12. Monopoly 的生产:MC=MR,难点在于 MR的计算(先算 TR,再MR) 非常重要 !!! 13. Monopoly 的图、Surplus 的影响 (DWL) 难点,Monopoly 同时和 Price ceiling 结合分析 Surplus 14. Subsidies 的 Surplus 的影响 15. Price control 的 Surplus 的影响 [14]Source: 8069期中押题.pdfΕχρ = Percentage change in quantity demanded of good x Percentage change in price of good y Top Professional Top Professional 独家复习资料,仅限内部学员学习使用,盗版必究 @ Learning Made Easy Top Professional @ Learning Made Easy Top Professional 独家复习资料,仅限内部学员学习使用,盗版必究 Elasticity >0,互为替代品;Elasticity <0,互补品 10. Given the information in table 2:

解析：

价格弹性公式： $$ Ed = \frac{%;\text{quantity change}}{%;\text{price change}} $$ 值>1为弹性大，<1为弹性小。
交叉价格弹性公式： $$ E_{x,y} = \frac{%;\Delta Q_x}{%;\Delta P_y} $$

0为替代品，<0为互补品。
典型陷阱：一定要看清“价格变动”影响的是本品（自弹性）还是相关商品（交叉弹性）；分子分母不要弄反[14]Source: 8069期中押题.pdfΕχρ = Percentage change in quantity demanded of good x Percentage change in price of good y Top Professional Top Professional 独家复习资料,仅限内部学员学习使用,盗版必究 @ Learning Made Easy Top Professional @ Learning Made Easy Top Professional 独家复习资料,仅限内部学员学习使用,盗版必究 Elasticity >0,互为替代品;Elasticity <0,互补品 10. Given the information in table 2:。

3. 考虑机会成本

考点定位： 决策过程中的无形代价分析 [4]Source: 8069期中押题.pdf次级知识点推荐: 1. 完全竞争市场和 Monopoly(垄断)的区别 2. 关于弹性的计算 3. 记住考虑 Opportunity Cost 考试趋向分析: 1. 选择题的比重上升,接近45~50分,难度加大,保分必备 2. 简答题比重减少,题量减少3小题左右,实际难度和上学期持平,拉开差距 Top Professional Top Professional 独家复习资料,仅限内部学员学习使用,盗版必究 @ Learning Made Easy

解析：

定义：机会成本是做出某一选择时，放弃的最大收益的那个选项。
答题建议：如题干提及“成本”但未给“机会成本”，需主动补述。

4. 税收影响分析（税负分担，政府收入，DWL等）

考点定位： 微观政策分析，有时结合图形与面积计算[1]Source: 8069期中押题.pdfA + B + D+ F+H A+B+C+D C + E+G + E + F + G + H c) The change in government revenue is -(B + F)+E, which could be positive or negative. This is because while the tax has been reduced, the quantity sold in the market has increased. d) The change in deadweight loss is negative, as it decreases by C+ E + G. the decrease in the deadweight loss because deadweight loss is positively related with the size of the tax. As tax declines, deadweight loss declines. e) The demand for cars in Victoria is probably fairly elastic since people could travel to nearby states to buy cars. (other explanations that are consistent with elastic demand are ok too). With elastic demand, car buyers will respond strongly to changes in prices. As illustrated in the graph, a more elastic demand curve, a greater increase in the quantity sold due to the tax and the smaller quantity sold associated with the initial tax. The greater the increase in the sellers supply and increase in the quantity sold due to the reduction in the tax will be, the bigger E will be, and smaller (B+F)). Thus, with this additional information, the decrease in the tax is more likely to increase government revenue. 答题总结:1. 一定要回答简答题中的定义;2. 尽量画图并且记得标上所有的符号和点;3.[7]Source: 8069期中押题.pdfTop Professional @ Learning Made Easy Top Professional 独家复习资料,仅限内部学员学习使用,盗版必究习题精讲知识点覆盖: 1. Tax: Who pay for the tax? 2. Price floor 的定义及影响 3. 消费者行为: MBx Px MBx = py 4. Demand curve 的移动原因以及形式 5. Supply curve 的移动原因及形式 6. Consumer Surplus, Producers Surplus, Total Surplus 的定义以及面积计算 [11]Source: 8069期中押题.pdfDemand Q2 Q1 Quantity of Cars Top Professional Top Professional 独家复习资料,仅限内部学员学习使用,盗版必究 @ Learning Made Easy Industry Price 52 51 T

解析：

分担原理：税收分担由弹性大小决定——谁弹性小，谁承担税负多。
收入和DWL分析：
- 税额越大，DWL越大，剩余损失面积也随之扩大。
- 政府收入=税率 × 销量。
画图提示：标注消费者/生产者剩余、政府收入和DWL。

5. 价格管制与补贴对福利的影响

考点定位： 分析政府干预对市场均衡、剩余的影响[6]Source: 8069期中押题.pdf7. Tax 的影响和弹性的关系,同时结合 Surplus、Tax revenue 的面积 8. 价格弹性(考察了互为替代品的交叉价格弹性的判定) 9. Economic Scale 的定义 10. 在完全竞争市场下,Firms 的 Short-term 和 Long-term 的情况 11. Monopoly 的特点,market power,自然垄断的定义 12. Monopoly 的生产:MC=MR,难点在于 MR的计算(先算 TR,再MR) 非常重要 !!! 13. Monopoly 的图、Surplus 的影响 (DWL) 难点,Monopoly 同时和 Price ceiling 结合分析 Surplus 14. Subsidies 的 Surplus 的影响 15. Price control 的 Surplus 的影响

解析：

价格上限/下限：上限形成短缺，下限形成过剩。
补贴：增加生产者剩余，政府支出=补贴金额×成交量。
图形法：多以三角形和矩形表示各类剩余变化区域。

6. 消费者行为&预算分配问题

考点定位： 边际效用/价格的等式使用[7]Source: 8069期中押题.pdfTop Professional @ Learning Made Easy Top Professional 独家复习资料,仅限内部学员学习使用,盗版必究习题精讲知识点覆盖: 1. Tax: Who pay for the tax? 2. Price floor 的定义及影响 3. 消费者行为: MBx Px MBx = py 4. Demand curve 的移动原因以及形式 5. Supply curve 的移动原因及形式 6. Consumer Surplus, Producers Surplus, Total Surplus 的定义以及面积计算 [8]Source: 8069期中押题.pdf6. If Sam consumes two goods Apples and Biscuits and the price of an apple is Pa= $5 and the price of a biscuit is P=$5 and the extra benefit Sam receives from one more apple is 4 and from one more biscuit is 2 then Sam should: a. buy more biscuits to increase his marginal benefits, and less apples. b. buy more biscuits and more apples. c. buy more apples and less biscuits. d. do none of the above, as we don't have enough information to determine his best option. 考点:消费者行为 Top Professional Top Professional 独家复习资料,仅限内部学员学习使用,盗版必究 @ Learning Made Easy Top Professional @ Learning Made Easy [17]Source: 8069期中押题.pdfTop Professional 独家复习资料,仅限内部学员学习使用,盗版必究 Po Top Professional @ Learning Made Easy Top Professional 独家复习资料,仅限内部学员学习使用,盗版必究 3. Jenny has $50 to spend on beans and shoes. The price of a can of beans is $5/can and the price of a pair of shoes is $10/pair. Given the information in the table below (table 1), how many cans of beans and pairs of shoes should Jenny buy? Cans of Beans Pairs of Shoes Quantity Total Benefit Quantity

解析：

公式：最优消费条件是 $$ \frac{MB_x}{P_x} = \frac{MB_y}{P_y} $$
步骤：1）算每一单位边际效用/价格，2）对比，3）优先分配预算给单位价值高的商品，直到等式成立或用完预算。

7. 规模经济（Returns to Scale）判断

考点定位： 生产理论，ATC变化判断 [3]Source: 8069期中押题.pdf20. 40 Average total cost 先下降后增加,ATC 下降时 increasing returns to scale; ATC 上升是 decreasing returns to scale Top Professional Top Professional 独家复习资料,仅限内部学员学习使用,盗版必究 @ Learning Made Easy Top Professional @ Learning Made Easy Top Professional 独家复习资料,仅限内部学员学习使用,盗版必究 11. Given the above graph, if a tax is placed on this good/service then: Price Supply [13]Source: 8069期中押题.pdfQuantity Total Cost a. The firm is experiencing decreasing returns to scale b. The firm is experiencing increasing returns to scale c. The firm is experiencing both increasing and decreasing returns to scale d. None of the above. 考点: Economy scale 的定义,取决于 ATC,所以现在表格的右侧计算出 Average Total cost Average total cost ATC in short run with small factory [18]Source: 8069期中押题.pdfc. In the short run, his economic profit may be less than zero and he should leave the industry immediately. d. In the long run, his economic profit will be zero and he should think about expanding the size of his firm. 考点:在完全竞争市场里,短期和长期的市场 Market Price mc Supply atc P1 p

解析：

判断公式：ATC下降——规模报酬递增；ATC上升——规模报酬递减。
答题技巧：一定要计算ATC，并结合数据表判断阶段。

8. 图形/面积题（剩余、DWL、税收等标注）

考点定位： 供需图解读能力[2]Source: 8069期中押题.pdf可以用见箭头符号表示增减、因为所以等;4,得分的关键在于是否逻辑正确,没有遗漏 Top Professional Top Professional 独家复习资料,仅限内部学员学习使用,盗版必究 @ Learning Made Easy Top Professional @ Learning Made Easy Top Professional 独家复习资料,仅限内部学员学习使用,盗版必究 7. From the information in figure 1 below we can see that: a. Consumer Surplus is $24, Producer Surplus is $9 and Total Surplus is $33. b. Consumer Surplus is $9, Producer Surplus is $24 and Total Surplus is $33. c. Consumer Surplus is $21, Producer Surplus is $12 and Total Surplus is $33.[5]Source: 8069期中押题.pdfDemand Top Professional @ Learning Made Easy Top Professional 独家复习资料,仅限内部学员学习使用,盗版必究 b) The following table shows the welfare impact of the change in the tax. OLD Ew CHANGE Consumer surplus A A + B + C [14]Source: 8069期中押题.pdfΕχρ = Percentage change in quantity demanded of good x Percentage change in price of good y Top Professional Top Professional 独家复习资料,仅限内部学员学习使用,盗版必究 @ Learning Made Easy Top Professional @ Learning Made Easy Top Professional 独家复习资料,仅限内部学员学习使用,盗版必究 Elasticity >0,互为替代品;Elasticity <0,互补品 10. Given the information in table 2:

解析：

必备要素：价格轴、数量轴、均衡点、税区、政府收入（矩形）、DWL（三角形）、CS/PS区域。
作图步骤：画2条或3条曲线，按变化“先旧后新”，用符号标注变化区。

9. 热点政策及市场变化（如热巧克力市场例题、冰淇淋市场）

考点定位： 结合当前事件、模拟政策冲击市场均衡分析[12]Source: 8069期中押题.pdf简答模板一: Question 2 Suppose we are analysing the market for hot chocolate. Explain the effect each of the following situations will have on either the demand or supply of hot chocolate. Explain also what the effect will be on equilibrium price and quantity. Please give your (short) answers using both words and supply-and-demand diagrams. a) Suppose the price of coffee, a substitute for hot chocolate, falls. b) The price of cocoa beans, an ingredient for making hot chocolate, increases. c) The Health Department of Australia announces that hot chocolate cures acne. Answer: a) The price of coffee, a substitute for hot chocolate, falls. 第一步先回答答案 The demand for a good is affected by changes in the prices of its related goods. Because coffee is a substitute for hot chocolate, the price of coffee decreases will decrease the demand for hot chocolate (or will lead to a decrease in demand for hot chocolate). Thus, the demand curve shifts to the left. At the old price, there will an excess of supply (supply surplus). Sellers respond by reducing the price. As the price reduces, it will lead to a reduction in the quantity supplied. At the same time, the change in the price will lead to an increase in the quantity demanded. These changes represent movements along the supply curve and the new demand curve, and they move the market towards a new equilibrium.[20]Source: 8069期中押题.pdfTop Professional 独家复习资料,仅限内部学员学习使用,盗版必究 c) The Health Department of Australia announces that hot chocolate cures acne. The news represents an increased benefit of hot chocolate. Thus, the news increases the demand for hot chocolate. Thus, the demand curve will shift and the direction of the shift is to the right. The forces of supply and demand will ensure the market reach a new equilibrium. The result is an increase in equilibrium price and an increase in equilibrium quantity, as shown in the graph Î 简答模板二: Question 2 Suppose there are 100 ice-cream shops operating in Canberra. Each shop has the usual U- shaped average-total-cost curve. The market demand curve for ice-cream slopes downwards and the market for ice-cream is in long run competitive equilibrium. a. Draw the current equilibrium, using graphs for the entire market and for an individual ice-cream shop. b. Now the city decides to restrict the number of ice-cream shops. The council passes a law that reduces the number of shops to only 80. What effect will this action have on the market and on an individual shop that is still operating? Use graphs to illustrate your answer. c. Suppose that the council decides to charge the 80 ice-cream shops a licence fee. How will this affect the number of ice-creams sold by an individual shop and the shop's profit? The council wants to raise as much revenue as possible and also wants to ensure that the 80 ice-cream shops remain in the city. At what level should the council set the lincence fee? Show the answer on your graph.

解析：

框架：1）变量变化——2）供/需增减/曲线移动——3）均衡点变化（P、Q方向）——4）简图、箭头标注。

答题小结与技巧：

定义全写：简答题先写出相关定义（如：完全竞争、垄断、弹性、机会成本等）。
逻辑链条清晰：答题顺序为现象—原理—过程—结果。
标注图形：作图时一定要标全所有要素和变化过程。
用术语和公式：公式、专业术语要出现，高分保障。
避免遗漏：分析题目时，注意每一步解释，不要有逻辑跳跃。

如需任何一道具体题目的详细逐步解法或作图示范，请直接告知题号！

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好的，以下是“8069期中押题.pdf”中常见考试题型代表题目的详细解析，侧重方法、公式与答题思路：

1. 完全竞争与垄断市场的区别【常考理论选择/简答题】

解析：

完全竞争市场特点：大量买卖者，产品同质，企业为“价格接受者”，无进入壁垒。
垄断市场特点：唯一卖方，强市场势力，有进入壁垒（如专利、规模优势），企业为“价格制定者”。
典型选择题会要求区分两者特征或判断某市场归属。
简答时，建议写明定义+特征对比表格[3]Source: 8069期中押题.pdf次级知识点推荐: 1. 完全竞争市场和 Monopoly(垄断)的区别 2. 关于弹性的计算 3. 记住考虑 Opportunity Cost 考试趋向分析: 1. 选择题的比重上升,接近45~50分,难度加大,保分必备 2. 简答题比重减少,题量减少3小题左右,实际难度和上学期持平,拉开差距 Top Professional Top Professional 独家复习资料,仅限内部学员学习使用,盗版必究 @ Learning Made Easy。

2. 弹性计算与替代/互补品判定【常考选择/计算题】

解析：

需求价格弹性公式： $$ E_d = \frac{%;\Delta Q}{%;\Delta P} $$
交叉价格弹性公式： $$ E_{x,y} = \frac{%;\Delta Q_x}{%;\Delta P_y} $$
- $E_{x,y} > 0$ → 替代品；$E_{x,y} < 0$ → 互补品[9]Source: 8069期中押题.pdfΕχρ = Percentage change in quantity demanded of good x Percentage change in price of good y Top Professional Top Professional 独家复习资料,仅限内部学员学习使用,盗版必究 @ Learning Made Easy Top Professional @ Learning Made Easy Top Professional 独家复习资料,仅限内部学员学习使用,盗版必究 Elasticity >0,互为替代品;Elasticity <0,互补品 10. Given the information in table 2:。

3. 机会成本概念及应用【常考基础判断/选择题】

解析：

机会成本是指在多种选择中，完成某事所放弃的最大收益的那一项。
典型选择或案例分析，如考“生产某产品时放弃了什么？”[3]Source: 8069期中押题.pdf次级知识点推荐: 1. 完全竞争市场和 Monopoly(垄断)的区别 2. 关于弹性的计算 3. 记住考虑 Opportunity Cost 考试趋向分析: 1. 选择题的比重上升,接近45~50分,难度加大,保分必备 2. 简答题比重减少,题量减少3小题左右,实际难度和上学期持平,拉开差距 Top Professional Top Professional 独家复习资料,仅限内部学员学习使用,盗版必究 @ Learning Made Easy。

4. 税收影响题型（税负分担、政府收入、死重损失DWL）【重点选择、图形与简答题】

解析：

5. 价格管制（Price Floor/Ceiling）、补贴影响【常见选择与分析题】

解析：

**价格上限（Ceiling）**易导致短缺；**价格下限（Floor）**则导致过剩。
补贴会提升生产者或消费者剩余，但增加政府支出。
答案通常结合剩余面积与福利变化分析区域[15]Source: 8069期中押题.pdfChange Supply Consume A+B+ C A -(B + C) A Price Floor r Surplus C。