下载文档原格式
曼昆《经济学原理》（第五版）习题解答第一篇导言第一章经济学十大原理复习题1．列举三个你在生活中面临的重要权衡取舍的例子。
答：①大学毕业后，面临着是否继续深造的选择，选择继续上学攻读研究生学位，就意味着在今后三年中放弃参加工作、赚工资和积累社会经验的机会；②在学习内容上也面临着很重要的权衡取舍，如果学习《经济学》，就要减少学习英语或其他专业课的时间；③对于不多的生活费的分配同样面临权衡取舍，要多买书，就要减少在吃饭、买衣服等其他方面的开支。
2．看一场电影的机会成本是什么?答：看一场电影的机会成本是在看电影的时间里做其他事情所能获得的最大收益，例如：看书、打零工。
3．水是生活必需的。
一杯水的边际利益是大还是小呢?答：这要看这杯水是在什么样的情况下喝，如果这是一个人五分钟内喝下的第五杯水，那么他的边际利益很小，有可能为负；如果这是一个极度干渴的人喝下的第一杯水，那么他的边际利益将会极大。
4．为什么决策者应该考虑激励?答：因为人们会对激励做出反应，而政策会影响激励。
如果政策改变了激励，它将使人们改变自己的行为，当决策者未能考虑到行为如何由于政策的原因而变化时，他们的政策往往会产生意想不到的效果。
5．为什么各国之间的贸易不像一场比赛一样有赢家和输家呢?答：因为贸易使各国可以专门从事自己最擅长的活动，并从中享有更多的各种各样的物品与劳务。
通过贸易使每个国家可供消费的物质财富增加，经济状况变得更好。
因此，各个贸易国之间既是竞争对手，又是经济合作伙伴。
在公平的贸易中是“双赢”或者“多赢”的结果。
6．市场中的那只“看不见的手”在做什么呢?答：市场中那只“看不见的手”就是商品价格，价格反映商品自身的价值和社会成本，市场中的企业和家庭在作出买卖决策时都要关注价格。
因此，他们也会不自觉地考虑自己行为的(社会)收益和成本。
从而，这只“看不见的手”指引着千百万个体决策者在大多数情况下使社会福利趋向最大化。
7．解释市场失灵的两个主要原因，并各举出一个例子。
第十一章公共物品和共有资源复习题1．解释一种物品有“排他性”的含义。
解释一种物品有“竞争性”的含义。
比萨饼有排他性吗?有竞争性吗?答：一种物品具有“排他性”是指可以阻止一个人使用一种物品时该物品的特性。
一种物品有竞争性是指一个人使用一种物品减少其他人使用该物品的特性。
比萨饼有排他性，只要不卖给某人比萨饼就可以阻止他使用。
比萨饼也有竞争性，一个人多吃一块比萨饼，会使其他人少享受一块。
2．给公共物品下定义并举出一个例子。
私人市场本身能提供这种物品吗?并解释之。
答：公共物品是既无排他性又无竞争性的物品，私人市场本身不能提供这种物品。
公共物品没有排他性，因此，无法对公共物品的使用者收费，在私人提供这种物品时就存在搭便车的激励，从而使私人提供者无利可图。
3．什么是公共物品的成本一收益分析?为什么它是重要的?进行这种分析困难吗?答：公共物品的成本一收益分析是提供一种公共物品的社会成本和社会收益比较的研究。
只有比较提供一种公共物品的成本与收益，政府才能决定是否值得提供这种公共物品。
公共物品的成本一收益分析是一项艰苦的工作。
因为所有的人都可以免费使用一种公共物品，没有判断这种公共物品价值的价格。
简单地问人们，他们对一种公共物品的评价是多少是不可靠的。
那些受益于该公共物品的人有夸大他们的利益的激励。
那些受害于该公共物品的人有夸大他们成本的激励。
4．给共有资源下定义并举出一个例子。
没有政府干预，人们使用这种物品会太多还是太少?为什么?答：共有资源是有竞争性但无排他性的物品。
没有政府干预，人们使用这种物品会太多。
因为不能向使用共有资源的人收费，而且，一个人对共有资源的使用会减少其他人的使用，所以，共有资源往往被过度使用。
问题与应用1．本书认为公共物品和共有资源都涉及外部性。
A．与公共物品相关的外部性一般是正的还是负的?用例子来回答。
自由市场的公共物品量一般是大于还是小于有效率的数量?答：与公共物品相关的外部性一般是负的。
第一章经济学十大原理问题与应用2．你正想决定是否去度假。
度假的大部分成本(机票、旅馆、放弃的工资)都用美元来衡量，但度假的收益是心理的。
你将如何比较收益与成本呢??答：这种心理上的收益可以用是否达到既定目标来衡量。
对于这个行动前就会作出的既定目标，我们一定有一个为实现目标而愿意承担的成本范围。
在这个可以承受的成本范围内，度假如果满足了既定目标，如：放松身心、恢复体力等等，那么，就可以说这次度假的收益至少不小于它的成本。
3．你正计划用星期六去从事业余工作，但一个朋友请你去滑雪。
去滑雪的真实成本是什么？现在假设你已计划这天在图书馆学习，这种情况下去滑雪的成本是什么？请解释之。
答：去滑雪的真实成本是周六打工所能赚到的工资，我本可以利用这段时间去工作。
如果我本计划这天在图书馆学习，那么去滑雪的成本是在这段时间里我可以获得的知识。
4．你在篮球比赛的赌注中赢了100美元。
你可以选择现在花掉它或在利率为5%的银行中存一年。
现在花掉100美元的机会成本是什么呢?答：现在花掉100 美元的机会成本是在一年后得到105 美元的银行支付(利息+本金)。
6．你的室友做饭比你好，但你打扫房间比你的室友快。
如果你的室友承担全部做饭工作，你承担全部打扫工作，那么你所要花费的时间比你们平均分摊两种家务时花费的时间多了还是少了？试举一个类似的例子，说明专业化和贸易如何使两个国家的状况变得更好。
答：我们俩各自承担自己擅长的工作比我们平均分摊两种家务时，我要花费的时间少了，因为娴熟的技巧使工作效率提高。
举例：假设A 国比B 国擅长生产丝绸，而B 国生产皮毛制品的效率比A 国高，如果A 国专门生产丝绸，B国专门生产皮毛制品，由于它们各自在相关生产上的优势，会使两种商品的生产率提高，有更多的丝绸和皮毛制品在市场上供应。
这样，A、B 两国间的专业分工和相互贸易使两国消费者有更多的丝绸和皮毛制品可供消费，两国的生活水平都提高了。
7．解释下列每一项政府活动的动机是关注平等还是关注效率。
Chapter 13Firms in Competitive MarketsM ULTIPLE C HOICE1. A market is competitive if(i) firms have the flexibility to price their own product.(ii) each buyer is small compared to the market.(iii) each seller is small compared to the market.a. (i) and (ii) onlyb. (i) and (iii) onlyc. (ii) and (iii) onlyd. All of the above are correct.ANSWER: c. (ii) and (iii) onlyTYPE: M DIFFICULTY: 2 SECTION: 14.12. When a firm has little ability to influence market prices it is said to be in what kind of a market?a. a competitive marketb. a strategic marketc. a thin marketd. a power marketANSWER: a. a competitive marketTYPE: M DIFFICULTY: 1 SECTION: 14.13. In a competitive market, the actions of any single buyer or seller willa. have a negligible impact on the market price.b. have little effect on overall production but will ultimately change final product price.c. cause a noticeable change in overall production and a change in final product price.d. adversely affect the profitability of more than one firm in the market.ANSWER: a. have a negligible impact on the market price.TYPE: M DIFFICULTY: 2 SECTION: 14.1Use the information in the table below to answer questions 4 through 7.Quantity Price1 132 133 134 135 136 137 138 139 134. The price and quantity relationship in the table is most likely that faced by a firm in aa. monopoly.b. concentrated market.c. competitive market.d. strategic market.ANSWER: c. competitive market.TYPE: M DIFFICULTY: 1 SECTION: 14.1405406 Chapter 14/Firms in Competitive Markets5. Over which range of output is average revenue equal to price?a. 1 to 5b. 3 to 7c. 5 to 9d. Average revenue is equal to price over the whole range of output.ANSWER: d. Average revenue is equal to price over the whole range of output.TYPE: M DIFFICULTY: 1 SECTION: 14.16. Over what range of output is marginal revenue declining?a. 1 to 6b. 3 to 7c. 7 to 9d. None; marginal revenue is constant over the whole range of output.ANSWER: d. None; marginal revenue is constant over the whole range of output.TYPE: M DIFFICULTY: 2 SECTION: 14.17. If the firm doubles its output from 3 to 6 units, total revenue willa. increase by less than $39.b. increase by exactly $39.c. increase by more than $39.d. It cannot be determined from the information provided.ANSWER: b. increase by exactly $39.TYPE: M DIFFICULTY: 1 SECTION: 14.18. For a firm in a perfectly competitive market, the price of the good is alwaysa. equal to marginal revenue.b. equal to total revenue.c. greater than average revenue.d. All of the above are correct.ANSWER: a. equal to marginal revenue.TYPE: M DIFFICULTY: 1 SECTION: 14.19. If a firm in a perfectly competitive market triples the number of units of output sold, then total revenue willa. more than triple.b. less than triple.c. exactly triple.d. All of the above are potentially true.ANSWER: c. exactly triple.TYPE: M DIFFICULTY: 1 SECTION: 14.110. Because the goods offered for sale in a competitive market are largely the same,a. there will be few sellers in the market.b. there will be few buyers in the market.c. buyers will have market power.d. sellers will have little reason to charge less than the going market price.ANSWER: d. sellers will have little reason to charge less than the going market price.TYPE: M DIFFICULTY: 1 SECTION: 14.111. Which of the following is NOT a characteristic of a perfectly competitive market?a. Firms are price takers.b. Firms have difficulty entering the market.c. There are many sellers in the market.d. Goods offered for sale are largely the same.ANSWER: b. Firms have difficulty entering the market.TYPE: M DIFFICULTY: 1 SECTION: 14.1Chapter 14/Firms in Competitive Markets 40712. When buyers in a competitive market take the selling price as given, they are said to bea. market entrants.b. monopolists.c. free riders.d. price takers.ANSWER: d. price takers.TYPE: M DIFFICULTY: 1 SECTION: 14.113. When firms are said to be price takers, it implies that if a firm raises its price,a. buyers will go elsewhere.b. buyers will pay the higher price in the short run.c. competitors will also raise their prices.d. firms in the industry will exercise market power.ANSWER: a. buyers will go elsewhere.TYPE: M DIFFICULTY: 1 SECTION: 14.114. Which of the following statements best reflects a price-taking firm?a. If the firm were to charge more than the going price, it would sell none of its goods.b. The firm has no incentive to charge less than the going price.c. The firm can sell as much as it wants to sell at the going price.d. All of the above are correct.ANSWER: d. All of the above are correct.TYPE: M DIFFICULTY: 2 SECTION: 14.115. In a competitive market, no single producer can influence the market price becausea. many other sellers are offering a product that is essentially identical.b. consumers have more influence over the market price than producers do.c. government intervention prevents firms from influencing price.d. producers agree not to change the price.ANSWER: a. many other sellers are offering a product that is essentially identical.TYPE: M DIFFICULTY: 2 SECTION: 14.116. A competitive firm might choose to set its price below the market price, becausea. this would result in higher average revenue.b. this would result in higher profits.c. this would result in lower total costs.d. None of the above are correct.ANSWER: d. None of the above are correct.TYPE: M DIFFICULTY: 2 SECTION: 14.117. Of the following characteristics of competitive markets, which are necessary for firms to be price takers?(i) There are many sellers.(ii) Firms can freely enter or exit the market.(iii) Goods offered for sale are largely the same.a. (i) and (ii) onlyb. (i) and (iii) onlyc. (ii) onlyd. All are necessary.ANSWER: b. (i) and (iii) onlyTYPE: M DIFFICULTY: 2 SECTION: 14.118. When a firm in a competitive market produces 10 units of output, it has a marginal revenue of $8.00. What would bethe firm’s total revenue when it produces 6 units of output?a. $4.80b. $6.00c. $48.00d. $60.00ANSWER: c. $48.00TYPE: M DIFFICULTY: 2 SECTION: 14.1408 Chapter 14/Firms in Competitive Markets19. When a firm in a competitive market receives $500 in total revenue, it has a marginal revenue of $10. What is theaverage revenue, and how many units were sold?a. $5 and 100b. $10 and 50c. $10 and 100d. The answer cannot be determined from the information given.ANSWER: b. $10 and 50TYPE: M DIFFICULTY: 2 SECTION: 14.120. Starting from a situation in which a firm in a competitive market produces and sells 500 door knobs for a price of$10 per doorknob, which of the follo wing events would decrease the firm’s average revenue?a. The firm increases its output above 500 doorknobs.b. The firm decreases its output below 500 doorknobs.c. The market price of doorknobs rises above $10.d. The market price of doorknobs falls below $10.ANSWER: d. The market price of door knobs falls below $10.TYPE: M DIFFICULTY: 1 SECTION: 14.221. Whenever a perfectly competitive firm chooses to change its level of output, holding the price of the productconstant, its marginal revenuea. increases if MR < ATC and decreases if MR > ATC.b. does not change.c. increases.d. decreases.ANSWER: b. does not change.TYPE: M DIFFICULTY: 1 SECTION: 14.122. If a firm in a competitive market reduces its output by 20 percent, then as a result the price of its output is likely toa. increase.b. remain unchanged.c. decrease by less than 20 percent.d. decrease by more than 20 percent.ANSWER: b. remain unchanged.TYPE: M DIFFICULTY: 1 SECTION: 14.123. Changes in the output of a perfectly competitive firm, without any change in the price of the product, will changethe firm’sa. total revenue.b. marginal revenue.c. average revenue.d. All of the above are correct.ANSWER: a. total revenue.TYPE: M DIFFICULTY: 2 SECTION: 14.124. When a profit-maximizing firm in a competitive market has zero economic profit, accounting profita. is negative (accounting losses).b. is positive.c. is also zero.d. could be positive, negative or zero.ANSWER: b. is positive.TYPE: M DIFFICULTY: 2 SECTION: 14.125. As a general rule, when accountants calculate profit they account for explicit costs but usually ignorea. certain outlays of money by the firm.b. implicit costs.c. operating costs.d. fixed costs.ANSWER: b. implicit costs.TYPE: M DIFFICULTY: 1 SECTION: 14.1Chapter 14/Firms in Competitive Markets 40926. In calculating accounting profit, accountants typically don’t includea. long-run costs.b. sunk costs.c. explicit costs of production.d. opportunity costs that do not involve an outflow of money.ANSWER: d. opportunity costs that do not involve an outflow of money.TYPE: M DIFFICULTY: 1 SECTION: 14.1Use the following information to answer questions 27 through 29.As part of an estate settlement Mary received $1 million. She decided to use the money to purchase a small business in Anywhere, USA. If Mary would have invested the $1 million in a risk-free bond fund she could have made $100,000 each year. She also quit her job with Inc. to devote all of her time to her new business; her salary at Inc. was $75,000 per year.27. At the end of the first year of operating her new business, Mary’s accountant reported an accounting profit of$150,000. What was Mary’s economic profit?a. $25,000 lossb. $50,000 lossc. $25,000 profitd. $150,000 profitANSWER: a. $25,000 lossTYPE: M DIFFICULTY: 2 SECTION: 14.128.What are Mary’s opportunity costs of operating her new business?a. $25,000b. $75,000c. $100,000d. $175,000ANSWER: d. $175,000TYPE: M DIFFICULTY: 2 SECTION: 14.129. How large would Mary’s accoun ting profits need to be to allow her to attain zero economic profit?a. $100,000b. $125,000c. $175,000d. $225,000ANSWER: c. $175,000TYPE: M DIFFICULTY: 2 SECTION: 14.130. The Wheeler Wheat Farm sells wheat to a grain broker in Seattle, Washington. Since the market for wheat isgenerally considered to be competitive, the Wheeler Farm does nota. choose the quantity of wheat to produce.b. choose the price at which it sells its wheat.c. have any fixed costs of production.d. All of the above are correct.ANSWER: b. choose the price at which it sells its wheat.TYPE: M DIFFICULTY: 1 SECTION: 14.131. In a competitive market,a. no single buyer or seller can influence the price of the product.b. there is a small number of sellers.c. the goods offered by the different sellers are markedly different.d. All of the above are correct.ANSWER: a. no single buyer or seller can influence the price of the product.TYPE: M DIFFICULTY: 1 SECTION: 14.1410 Chapter 14/Firms in Competitive Markets32. In a competitive market,a. each seller can sell all he wants to sell at the going price.b. buyers and sellers are price takers.c. the goods offered by the different sellers are largely the same.d. All of the above are correct.ANSWER: d. All of the above are correct.TYPE: M DIFFICULTY: 1 SECTION: 14.133. If ABC Company sells its product in a competitive market, thena. the price of that product depends on the quantity of the product that ABC Company produces and sells.b. ABC Company’s total revenue is proportional to its quantity of output.c. ABC Company’s total cost is proportional to its quantity of output.d. ABC Company’s total revenue is equal to its average revenue.ANSWER: b. ABC Company’s total revenue is proportional to its quantity of output.TYPE: M DIFFICULTY: 2 SECTION: 1.4134. Which of the following expressions is correct for a competitive firm?a. Profit = Total revenue – Total cost.b. Marginal revenue = (Change in total revenue)/(Change in quantity of output).c. Average revenue = Total revenue/Quantity of output.d. All of the above are correct.ANSWER: d. All of the above are correct.TYPE: M DIFFICULTY: 2 SECTION: 14.135. For a competitive firm,a. Total revenue = Average revenue.b. Total revenue = Marginal revenue.c. Total cost = Marginal revenue.d. Average revenue = Marginal revenue.ANSWER: d. Average revenue = Marginal revenue.TYPE: M DIFFICULTY: 1 SECTION: 14.136. For a competitive firm,a. average revenue equals the price of the good, but marginal revenue is different.b. marginal revenue equals the price of the good, but average revenue is different.c. average revenue equals marginal revenue, but the price of the good is different.d. average revenue, marginal revenue, and the price of the good are all equal to one another.ANSWER: d. average revenue, marginal revenue, and the price of the good are all equal to one another.TYPE: M DIFFICULTY: 2 SECTION: 14.137. If a competitive firm is (i) selling 1,000 units of its product at a price of $9 per unit and (ii) earning a positive profit,thena. its total cost is less than $9,000.b. its marginal revenue is less than $9.c. its average revenue is greater than $9.d. All of the above are correct.ANSWER: a. its total cost is less than $9,000.TYPE: M DIFFICULTY: 2 SECTION: 14.138. When a competitive firm triples the amount of output it sells,a. its total revenue triples.b. its average revenue triples.c. its marginal revenue triples.d. All of the above are correct.ANSWER: a. its total revenue triples.TYPE: M DIFFICULTY: 2 SECTION: 14.1Chapter 14/Firms in Competitive Markets 41139. Total profit for a firm is calculated bya. marginal revenue minus average cost.b. average revenue minus average cost.c. marginal revenue minus marginal cost.d. total revenue minus total cost.ANSWER: d. total revenue minus total cost.TYPE: M DIFFICULTY: 1 SECTION: 14.2Use the information for a competitive firm in the table below to answer questions 40 through 45.Quantity Total Revenue Total Cost0 $ 0 $ 101 9 142 18 193 27 254 36 325 45 406 54 497 63 598 72 709 81 8240. At a production level of 4 units which of the following is true?a. Marginal cost is $6.b. Total revenue is greater than variable cost.c. Marginal revenue is less than marginal cost.d. All of the above are correct.ANSWER: b. Total revenue is greater than variable cost.TYPE: M DIFFICULTY: 2 SECTION: 14.241. At which quantity of output is marginal revenue equal to marginal cost?a. 3b. 6c. 8d. All of the above are correct.ANSWER: b. 6TYPE: M DIFFICULTY: 2 SECTION: 14.242. If this firm chooses to maximize profit it will choose a level of output where marginal cost is equal toa. 6.b. 7.c. 8.d. 9.ANSWER: d. 9.TYPE: M DIFFICULTY: 2 SECTION: 14.243. The maximum profit available to this firm isa. $5.b. $4.c. $3.d. $2.ANSWER: a. $5.TYPE: M DIFFICULTY: 1 SECTION: 14.2412 Chapter 14/Firms in Competitive Markets44. If the firm finds that its marginal cost is $11, it shoulda. increase production to maximize profit.b. increase the price of the product to maximize profit.c. advertise to attract additional buyers to maximize profit.d. None of the above are correct.ANSWER: d. None of the above are correct.TYPE: M DIFFICULTY: 2 SECTION: 14.245. If the firm finds that its marginal cost is $5, it shoulda. reduce fixed costs by lowering production.b. increase production to maximize profit.c. decrease production to maximize profit.d. maintain its current level of production to maximize profit.ANSWER: b. increase production to maximize profit.TYPE: M DIFFICULTY: 2 SECTION: 14.246. The Wheeler Wheat Farm sells wheat to a grain broker in Seattle, Washington. Since the market for wheat isgenerally considered to be competitive, the Wheeler Wheat Farm maximizes its profit by choosinga. to produce the quantity at which average total cost is minimized.b. to produce the quantity at which average fixed cost is minimized.c. to sell its wheat at a price where marginal cost is equal to average total cost.d. the quantity at which market price is equal to the farm’s marginal cost of production.ANSWER: d. the quantity a t which market price is equal to the farm’s marginal cost of production.TYPE: M DIFFICULTY: 2 SECTION: 14.247. Comparison of marginal revenue to marginal cost(i) reveals the contribution of the last unit of production to total profit.(ii) is helpful in making profit-maximizing production decisions.(iii) tells a firm whether its fixed costs are too high.a. (i) onlyb. (i) and (ii) onlyc. (ii) and (iii) onlyd. All of the above are correct.ANSWER: b. (i) and (ii) onlyTYPE: M DIFFICULTY: 2 SECTION: 14.248. If marginal cost exceeds marginal revenue, the firma. is most likely to be at a profit-maximizing level of output.b. should increase the level of production to maximize its profit.c. must be experiencing losses.d. may still be earning a profit.ANSWER: d. may still be earning a profit.TYPE: M DIFFICULTY: 2 SECTION: 14.249. When marginal revenue equals marginal cost, the firma. should increase the level of production to maximize its profit.b. may be minimizing its losses, rather than maximizing its profit.c. must be generating economic profits.d. must be generating economic losses.ANSWER: b. may be minimizing its losses, rather than maximizing its profit.TYPE: M DIFFICULTY: 2 SECTION: 14.250. When managers of firms think at the margin and make incremental adjustments to the level of production, they arenaturally led to a level of production wherea. average variable cost exceeds marginal cost.b. total cost is less than average revenue.c. costs are minimized.d. profit is maximized.ANSWER: d. profit is maximized.TYPE: M DIFFICULTY: 2 SECTION: 14.2Chapter 14/Firms in Competitive Markets 41351. As a general rule, profit-maximizing producers in a competitive market produce output at a point wherea. marginal cost is increasing.b. marginal cost is decreasing.c. marginal revenue is increasing.d. price is less than marginal revenue.ANSWER: a. marginal cost is increasing.TYPE: M DIFFICULTY: 2 SECTION: 14.2The graph below depicts the cost structure for a firm in a competitive market. Use the graph to answer questions 52 through 55.Note: On the above diagram, change the vertical-axis labels from MC1 to P1, MC2 to P2, etc.52.When price is equal to P3, the profit-maximizing firm will produce what level of output?a. Q1b. Q2c. Q3d. Q4ANSWER: c. Q3TYPE: M DIFFICULTY: 2 SECTION: 14.253. When market price is at P2, a firm producing output level Q1 would experiencea. profits equal to (P2– P1) ⨯ Q1.b. losses equal to (P2 –P1) ⨯ Q1.c. losses because P2 < ATC at output level Q1.d. zero profits.ANSWER: c. losses because P2 < ATC at output level Q1.TYPE: M DIFFICULTY: 2 SECTION: 14.254. When market price is at P4, a profit-maximizing firm will produce what level of output?a. Q1b. Q2c. Q3d. Q4ANSWER: d. Q4TYPE: M DIFFICULTY: 2 SECTION: 14.2414 Chapter 14/Firms in Competitive Markets55. When the price is P2 and the firm maximizes its profit or minimizes its loss, the firma. experiences a positive profit.b. experiences a zero profit.c. experiences a loss, but continues to operate.d. shuts down.ANSWER: b. experiences a zero profit.TYPE: M DIFFICULTY: 2 SECTION: 14.256. When calculating marginal cost, what must the firm know?a. sunk costb. variable costc. fixed costd. All of the above are correct.ANSWER: b. variable costTYPE: M DIFFICULTY: 2 SECTION: 14.257. The additional revenue a firm in a competitive market receives if it increases its production by one unit equals itsa. marginal revenue.b. average revenue.c. price per unit of output.d. All of the above are correct.ANSWER: d. All of the above are correct.TYPE: M DIFFICULTY: 2 SECTION: 14.2The graph below depicts the cost structure for a firm in a competitive market. Use the graph to answer questions 58 through 61.58.When price rises from P2 to P3, the firm finds thata. marginal cost exceeds marginal revenue at a production level of Q2.b. if it produces at output level Q3 it will earn a positive profit.c. expanding output to Q4 would leave the firm with losses.d. All of the above are correct.ANSWER: c. expanding output to Q4 would leave the firm with losses.TYPE: M DIFFICULTY: 2 SECTION: 14.259. When price falls from P3 to P1, the firm finds thata. fixed cost is higher at a production level of Q1 than it is at Q3.b. it should produce Q1 units of output.c. it should produce Q3 units of output.d. it is unwilling to produce any output.ANSWER: d. it is unwilling to produce any output.TYPE: M DIFFICULTY: 2 SECTION: 14.260. When price rises from P3 to P4, the firm finds thata. fixed costs are lower at a production level of Q4.b. it can earn a positive profit by increasing production to Q4.c. profit is maximized at a production level of Q3.d. average revenue exceeds marginal revenue at a production level of Q4.ANSWER: b. it can earn a positive profit by increasing production to Q4.TYPE: M DIFFICULTY: 2 SECTION: 14.261. Which of the following statements best reflects the situation faced by the firm when price falls from P4 to P2?a. Average total cost is lower than at the previous level of output so it increases production.b. The firm will earn profit equal to (P4– P2) Q2.c. Marginal revenue is lower than marginal cost at the previous level of output, so it decreases production.d. Marginal revenue is higher than marginal cost at the previous level of output, so it increases production. ANSWER: c. Marginal revenue is lower than marginal cost at the previous level of output, so it decreases production. TYPE: M DIFFICULTY: 2 SECTION: 14.262. A profit-maximizing firm in a competitive market will always make marginal adjustments to production as long asa. average revenue is greater than average total cost.b. average revenue is equal to marginal cost.c. marginal cost is greater than average total cost.d. price is above or below marginal cost.ANSWER: d. price is above or below marginal cost.TYPE: M DIFFICULTY: 2 SECTION: 14.263. When price is greater than marginal cost for a firm in a competitive market,a. marginal cost must be falling.b. the firm must be minimizing its losses.c. there are opportunities to increase profit by increasing production.d. the firm should decrease output to maximize profit.ANSWER: c. there are opportunities to increase profit by increasing production.TYPE: M DIFFICULTY: 2 SECTION: 14.264. The short-run supply curve for a firm in a perfectly competitive market isa. likely to be horizontal.b. likely to slope downward.c. determined by forces external to the firm.d. its marginal cost curve (above average variable cost).ANSWER: d. its marginal cost curve (above average variable cost).TYPE: M DIFFICULTY: 2 SECTION: 14.265. When a perfectly competitive firm makes a decision to shut down, it is most likely thata. marginal cost is above average variable cost.b. marginal cost is above average total cost.c. price is below the minimum of average variable cost.d. fixed costs exceed variable costs.ANSWER: c. price is below the minimum of average variable cost.TYPE: M DIFFICULTY: 2 SECTION: 14.266. When a firm makes a short-run decision not to produce anything during a specified period of time because ofcurrent market conditions, the firm is said toa. shut down.b. exit.c. withdraw.d. leave the industry.ANSWER: a. shut down.TYPE: M DIFFICULTY: 1 SECTION: 14.267. Firms that shut down in the short run still have to pay theira. variable costs.b. fixed costs.c. total cost.d. All of the above are correct.ANSWER: b. fixed costs.TYPE: M DIFFICULTY: 1 SECTION: 14.268. When total revenue is less than variable costs, a firm in a competitive market willa. continue to operate as long as average revenue exceeds marginal cost.b. continue to operate as long as average revenue exceeds average fixed cost.c. shut down.d. always exit the industry.ANSWER: c. shut down.TYPE: M DIFFICULTY: 2 SECTION: 14.269. When price is below average variable cost, a firm in a competitive market willa. shut down and incur fixed costs.b. shut down and incur both variable and fixed costs.c. continue to operate as long as average revenue exceeds marginal cost.d. continue to operate as long as average revenue exceeds average fixed cost.ANSWER: a. shut down and incur fixed costs.TYPE: M DIFFICULTY: 2 SECTION: 14.270. In 1999, sheepherders in the western United States slaughtered 10,000 sheep and buried them in large open pitsrather than truck them to the market to be sold. This behavior is most likely explained bya. sheepherders making a shut-down decision to save the variable cost of transporting sheep to a slaughter house.b. sheepherders making an exit decision to recover the fixed cost of raising the sheep.c. the rising marginal cost of producing sheep.d. irrational behavior of sheepherders.ANSWER: a. sheepherders making a shut-down decision to save the variable cost of transporting sheep to a slaughter house.TYPE: M DIFFICULTY: 2 SECTION: 14.2The figure below depicts the cost structure of a profit-maximizing firm in a competitive market. Use the figure to answer questions 71 and 72.71.Which line segment best reflects the short-run supply curve for this firm?a. BCDb. CDc. DEd. None of the above are correct.ANSWER: d. None of the above are correct.TYPE: M DIFFICULTY: 2 SECTION: 14.272. If the firm is in a short-run position where P < AVC, it is most likely to be on what segment of its supply curve?a. BCb. CDc. DEd. None of the above are correct.ANSWER: d. None of the above are correct.TYPE: M DIFFICULTY: 2 SECTION: 14.2The figure below depicts the cost structure of a profit-maximizing firm in a competitive market. Use the figure to answer questions 73 and 74.73.Which line segment best reflects the long-run supply curve for this firm?a. ABb. BCc. CDd. None of the above, the long-run supply curve requires knowledge of the average variable cost structure. ANSWER: c. CDTYPE: M DIFFICULTY: 2 SECTION: 14.274. This firm will exit the market for any price on the line segmenta. AB.b. BC.c. CD.d. None of the above are correct.ANSWER: a. AB.TYPE: M DIFFICULTY: 2 SECTION: 14.275. When economists refer to a production cost that has already been committed and cannot be recovered, they use theterma. implicit cost.b. explicit cost.c. variable cost.d. sunk cost.ANSWER: d. sunk cost.TYPE: M DIFFICULTY: 1 SECTION: 14.276. A profit-maximizing firm in a competitive market produces small rubber balls. When the market price for smallrubber balls falls below the minimum of its average total cost, but still lies above the minimum of average variable cost, the firma. will experience losses but it will continue to produce rubber balls.b. will shut down.c. will be earning both economic and accounting profits.d. should raise the price of its product.ANSWER: a. will experience losses but it will continue to produce rubber balls.TYPE: M DIFFICULTY: 2 SECTION: 14.2。
1．企业总收益、利润和总成本之间的关系是什么?答：企业利润＝总收益－总成本2．举出一个会计师不算作成本的机会成本的例子。
为什么会计师不考虑这种成本?答：企业家花时间和精力经营管理企业，他的机会成本是从事其他工作所能赚到的工资。
这种机会成本会计师不记作成本。
因为会计师分析经营活动的依据是货币的流人和流出，隐性机会成本不引起企业的货币流动。
因此，会计师不衡量它。
3．什么是边际产量，边际产量递减意味着什么?答：边际产量是增加一单位投入所引起的产量的增加。
如果出现边际产量递减，则意味着该企业的生产设备已经得到充分利用，只有增加工人才能生产更多的产品。
但新工人不得不在拥挤的条件下工作，而且可能不得不等待使用设备。
4．画出表示劳动的边际产量递减的生产函数。
画出相关的总成本曲线。
(在这两种情况下，都要标明坐标轴代表什么。
)解释你所画出的两个曲线的形状。
答：生产函数表示雇佣的工人数量和生产量之间的关系。
随着工人数量增加，生产函数变得增加，生产函数73变得平坦，这反映了边际产量递减。
由于边际产量递减，边际成本递增，随着产量增加，总成本曲线变得较为陡峭。
图13－1 劳动的边际产量递减的生产函数图13－2 总成本曲线5．叙述总成本、平均总成本和边际成本的定义。
它们之间的关系是怎样的?答：总成本是指企业购买生产投入支付的量。
平均总成本是总成本除以产量。
边际成本指额外－单位产量所引起的总成本的增加。
平均总成本＝总成本/产量边际成本＝总成本变动量/产量变动量6．画出一个典型企业的边际成本和平均总成本曲线。
解释为什么这些曲线的形状是这样，以及为什么在那一点相交。
答：74图13－3 典型企业的边际成本和平均总成本典型企业的边际成本曲线呈U 型。
因为企业在刚开始时，生产能力有剩余，增加一单位的投入量，边际产量会高于前一单位的投入，这样就出现一段边际成本下降。
生产能力全部被利用之后，再增加边际投入，就会出现边际产量递减，边际成本递增。
第一篇导言复习题第一章宏观经济学的科学1、解释宏观经济学和微观经济学之间的差距，这两个领域如何相互关联？【答案】微观经济学研究家庭和企业如何作出决策以及这些决策在市场上的相互作用。
微观经济学的中心原理是家庭和企业的最优化——他们在目的和所面临的约束条件下可以让自己的境况更好。
而相对的，宏观经济学研究经济的整体情况，它主要关心总产出、总就业、一般物价水平和国际贸易等问题，以及这些宏观指标的波动趋势与规律。
应该看到，宏观经济学研究的这些宏观经济变量是以经济体系中千千万万个体家庭和企业之间的相互作用所构成的。
因此，微观经济决策总是构成宏观经济模型的基础，宏观经济学必然依靠微观经济基础。
2、为什么经济学家建立模型？【答案】一般来说，模型是对某些具体事物的抽象，经济模型也是如此。
经济模型可以简洁、直接地描述所要研究的经济对象的各种关系。
这样，经济学家可以依赖模型对特定的经济问题进行研究；并且，由于经济实际不可控，而模型是可控的，经济学家可以根据研究需要，合理、科学的调整模型来研究各种经济情况。
另外，经济模型一般是数学模型，而数学是全世界通用的科学语言，使用规范、标准的经济模型也有利于经济学家正确表达自己的研究意图，便于学术交流。
3、什么是市场出清模型？什么时候市场出清的假设是适用的？【答案】市场出清模型就是供给与需求可以在价格机制调整下很快达到均衡的模型。
市场出清模型的前提条件是价格是具有伸缩性的（或弹性）。
但是，我们知道价格具有伸缩性是一个很强的假设，在很多实际情况下，这个假设都是不现实的。
比如：劳动合同会使劳动力价格在一段时期内具有刚性。
因此，我们必须考虑什么情况下价格具有伸缩性是合适的。
现在一般认为，在研究长期问题时，假设价格具有伸缩性是合理的；而在研究短期问题时，最好假设价格具有刚性。
因为，从长期看，价格机制终将发挥作用，使市场供需平衡，即市场出清，而在短期，价格机制因其他因素制约，难以很快使市场出清。
第13章生产和成本(一)单项选择题1.总产量曲线的斜率是（ C ）A.总产量B.平均产量C.边际产量D.以上都不是2.当TP下降时，（D ）A.AP L递增B.AP L为零C.MP L为零D.MP L为负3.当AP L为正且递减时，MP L是（ A ）A.递减B.负的C.零D.以上任何一种4.生产过程中某一可变要素的收益递减，这意味着（ B）A.可变要素投入量的增长和产量的增长等幅变化B.产量的增长幅度小于可变要素投入量的增长幅度C. 可变要素投入量的增长幅度小于产量的增长幅度D产量的增长幅度大于可变要素投入量的增长幅度5.某厂商每年从企业的总收入中取出一部分作为自己所提供的生产要素的报酬，这部分资金被视为（B ）。
A.显性成本B.隐性成本C.经济利润 D生产成本6.对应于边际报酬的递增阶段，STC曲线（C ）。
A.以递增的速率上升B. 以递增的速率下降C. 以递减的速率上升 D以递减的速率下降7.短期平均成本曲线成为U形的原因与（C ）有关A.规模报酬B.外部经济与不经济C.要素的边际报酬 D固定成本与可变成本所占比例8.在从原点出发的射线与TC 曲线的相切的产量上，必有（ D）。
A.AC值最小B.AC=MCC.MC曲线处于上升段D.A、B、C、9.如果生产10单位产品的总成本是100美元，第11单位产品的边际成本是21美元，那么（ C）。
A.第11单位产品TVC是21美元B.第10单位产品的边际成本是大于21美元C.11个产品的平均成本是11美元D第12单位产品的平均成本是21美元10.当边际成本小于平均成本时，产量的进一步增加将导致（ B）。
A.平均成本上升B.平均可变成本可能上升也可能下降C.总成本下降D平均可变成本一定是处于减少的状态11.长期平均成本曲线呈U型原因是（A ）。
A.规模报酬的变化所致B.外部经济与不经济所致C.生产要素的边际生产率所致 D固定成本与可变成本所占比重所致12.如果一个厂商的生产是处于规模报酬不变的阶段，则其LAC曲线一定是处于（ C）。
Problems and Applicat ions1. a. opportunity cost; b. average total cost; c. fixed cost; d. variable cost; e. total cost;f. marginal cost.2. a. The opportunity cost of something is what must be forgone to acquire it.b. The opportunity cost of running the hardware store is $550,000, consisting of$500,000 to rent the store and buy the stock and a $50,000 opportunity cost,since your aunt would quit her job as an accountant to run the store. Sincethe total opportunity cost of $550,000 exceeds revenue of $510,000, your auntshouldn't open the store, as her profit would be negative she would losemoney.3. a. Since you'd have to pay for room and board whether you went to college or not,that portion of your college payment is not an opportunity cost.b. The explicit opportunity cost is the cost of tuition.c. An implicit opportunity cost is the cost of your time. You could work at a jobfor pay rather than attend college. The wages you give up represent anopportunity cost of attending college.4. a. The following table shows the marginal product of each hour spent fishing:b. Figure 13-7 graphs the fisherman's production function. The productionfunction becomes flatter as the number of hours spent fishing increases,illustrating diminishing marginal product.Figure 13-7c. The table shows the fixed cost, variable cost, and total cost of fishing. Figure13-8 shows the fisherman's total-cost curve. It slopes up because catchingadditional fish takes additional time. The curve is convex because there arediminishing returns to fishing time each additional hour spent fishing yieldsfewer additional fish.5. Here’s the table of costs:a. See table for marginal product. Marginal product rises at first, then declinesbecause of diminishing marginal product.b. See table for total cost.c. See table for average total cost. Average total cost is U-shaped. Whenquantity is low, average total cost declines as quantity rises; when quantity ishigh, average total cost rises as quantity rises.d. See table for marginal cost. Marginal cost is also U-shaped.e. When marginal product is rising, marginal cost is falling, and vice versa.f. When marginal cost is less than average total cost, average total cost is falling;when marginal cost is greater than average total cost, average total cost isrising.6. Fixed costs include the cost of owning or renting a car to deliver the bagels and thecost of advertising; they're fixed costs because they don't vary with output. Variable costs include the cost of the bagels and gas for the car, since those costs will increase as output increases.7. a. The fixed cost is 300, since fixed cost equals total cost minus variable cost.b.Marginal cost equals the change in total cost or the change in variable cost.That's because total cost equals variable cost plus fixed cost and fixed costdoesn't change as the quantity changes. So as quantity increases, theincrease in total cost equals the increase in variable cost and both are equal tomarginal cost.8. a. The fixed cost of setting up the lemonade stand is $200. The variable costper cup is 50 cents.Figure 13-9b. The following table shows total cost, average total cost, and marginal cost.These are plotted in Figure 13-9.9. The following table illustrates average fixed cost (AFC), average variable cost (AVC),and average total cost (ATC) for each quantity. The efficient scale is 4 houses permonth, since that minimizes average total cost.10. a. The following table shows average variable cost (AVC), average total cost (ATC),and marginal cost (MC) for each quantity.b. Figure 13-10 graphs the three curves. The margi nal cost curve is below theaverage total cost curve when output is less than 4, as average total cost isdeclining. The marginal cost curve is above the average total cost curvewhen output is above 4, as average total cost is rising. The marginal costcurve is always above the average variable cost curve, and average variablecost is always increasing.Figure 13-1011. The following table shows quantity (Q), total cost (TC), and average total cost (ATC)for the three firms:Firm A has economies of scale since average total cost declines as output increases.Firm B has diseconomies of scale since average total cost rises as output rises. Firm C has economies of scale for output from 1 to 3, then diseconomies of scale for greater levels of output.。
