Chapter 7_ Production Function

A n s w e r s t o T e x t b o o k Q u e s t i o n s a n d P r o b l e m s CHAPTER 7?Unemployment and the Labor MarketQuestions for Review1. The rates of job separation and job finding determine the natural rate of unemployment. The rate of jobseparation is the fraction of people who lose their job each month. The higher the rate of job separation, the higher the natural rate of unemployment. The rate of job finding is the fraction of unemployed people who find a job each month. The higher the rate of job finding, the lower the natural rate ofunemployment.2. Frictional unemployment is the unemployment caused by the time it takes to match workers and jobs.Finding an appropriate job takes time because the flow of information about job candidates and job vacancies is not instantaneous. Because different jobs require different skills and pay different wages, unemployed workers may not accept the first job offer they receive.In contrast, structural unemployment is the unemployment resulting from wage rigidity and job rationing. These workers are unemployed not because they are actively searching for a job that best suits their skills (as in the case of frictional unemployment), but because at the prevailing real wage the quantity of labor supplied exceeds the quantity of labor demanded. If the wage does not adjust to clear the labor market, then these workers must wait for jobs to become available. Structural unemployment thus arises because firms fail to reduce wages despite an excess supply of labor.3. The real wage may remain above the level that equilibrates labor supply and labor demand because ofminimum wage laws, the monopoly power of unions, and efficiency wages.Minimum-wage laws cause wage rigidity when they prevent wages from falling to equilibrium levels. Although most workers are paid a wage above the minimum level, for some workers, especially the unskilled and inexperienced, the minimum wage raises their wage above the equilibrium level. It therefore reduces the quantity of their labor that firms demand, and creates an excess supply ofworkers, which increases unemployment.The monopoly power of unions causes wage rigidity because the wages of unionized workers are determined not by the equilibrium of supply and demand but by collective bargaining between union leaders and firm management. The wage agreement often raises the wage above the equilibrium level and allows the firm to decide how many workers to employ. These high wages cause firms to hire fewer workers than at the market-clearing wage, so structural unemployment increases.Efficiency-wage theories suggest that high wages make workers more productive. The influence of wages on worker efficiency may explain why firms do not cut wages despite an excess supply of labor. Even though a wage reduction decreases th e firm’s wage bill, it may also lower workerproductivity and therefore the firm’s profits.4. Depending on how one looks at the data, most unemployment can appear to be either short term orlong term. Most spells of unemployment are short; that is, most of those who became unemployed find jobs quickly. On the other hand, most weeks of unemployment are attributable to the small number of long-term unemployed. By definition, the long-term unemployed do not find jobs quickly, so they appear on unemployment rolls for many weeks or months.5. Europeans work fewer hours than Americans. One explanation is that the higher income tax rates inEurope reduce the incentive to work. A second explanation is a larger underground economy in Europe as a result of more people attempting to evade the high tax rates. A third explanation is the greater importance of unions in Europe and their ability to bargain for reduced work hours. A final explanation is based on preferences, whereby Europeans value leisure more than Americans do, and therefore elect to work fewer hours.Problems and Applications1. a. In the example that follows, we assume that during the school year you look for a part-time job,and that, on average, it takes 2 weeks to find one. We also assume that the typical job lasts 1semester, or 12 weeks.b. If it takes 2 weeks to find a job, then the rate of job finding in weeks isf = (1 job/2 weeks) = 0.5 jobs/week.If the job lasts for 12 weeks, then the rate of job separation in weeks iss = (1 job/12 weeks) = 0.083 jobs/week.c. From the text, we know that the formula for the natural rate of unemployment is(U/L) = [s/(s + f )],where U is the number of people unemployed, and L is the number of people in the labor force.Plugging in the values for f and s that were calculated in part (b), we find(U/L) = [0.083/(0.083 + 0.5)] = 0.14.Thus, if on average it takes 2 weeks to find a job that lasts 12 weeks, the natural rate ofunemployment for this population of college students seeking part-time employment is 14 percent.2. Call the number of residents of the dorm who are involved I, the number who are uninvolved U, and thetotal number of students T = I + U. In steady state the total number of involved students is constant.For this to happen we need the number of newly uninvolved students, (0.10)I, to be equal to thenumber of students who just became involved, (0.05)U. Following a few substitutions:(0.05)U = (0.10)I= (0.10)(T – U),soWe find that two-thirds of the students are uninvolved.3. To show that the unemployment rate evolves over time to the steady-state rate, let’s begin by defininghow the number of people unemployed changes over time. The change in the number of unemployed equals the number of people losing jobs (sE) minus the number finding jobs (fU). In equation form, we can express this as:U t + 1–U t= ΔU t + 1 = sE t–fU t.Recall from the text that L = E t + U t, or E t = L –U t, where L is the total labor force (we will assume that L is constant). Substituting for E t in the above equation, we findΔU t + 1 = s(L –U t) –fU t.Dividing by L, we get an expression for the change in the unemployment rate from t to t + 1:ΔU t + 1/L = (U t + 1/L) – (U t/L) = Δ[U/L]t + 1 = s(1 –U t/L) –fU t/L.Rearranging terms on the right side of the equation above, we end up with line 1 below. Now take line1 below, multiply the right side by (s + f)/(s + f) and rearrange terms to end up with line2 below:Δ[U/L]t + 1= s – (s + f)U t/L= (s + f)[s/(s + f) – U t/L].The first point to note about this equation is that in steady state, when the unemployment rate equals its natural rate, the left-hand side of this expression equals zero. This tells us that, as we found in the text, the natural rate of unemployment (U/L)n equals s/(s + f). We can now rewrite the above expression, substituting (U/L)n for s/(s + f), to get an equation that is easier to interpret:Δ[U/L]t + 1 = (s + f)[(U/L)n–U t/L].This expression shows the following:? If U t/L > (U/L)n (that is, the unemployment rate is above its natural rate), then Δ[U/L]t + 1 is negative: the unemployment rate falls.? If U t/L < (U/L)n (that is, the unemployment rate is below its natural rate), then Δ[U/L]t + 1 is positive: the unemployment rate rises.This process continues until the unemployment rate U/L reaches the steady-state rate (U/L)n.4. Consider the formula for the natural rate of unemployment,If the new law lowers the chance of separation s, but has no effect on the rate of job finding f, then the natural rate of unemployment falls.For several reasons, however, the new law might tend to reduce f. First, raising the cost of firing might make firms more careful about hiring workers, since firms have a harder time firing workers who turn out to be a poor match. Second, if job searchers think that the new legislation will lead them to spend a longer period of time on a particular job, then they might weigh more carefully whether or not to take that job. If the reduction in f is large enough, then the new policy may even increase the natural rate of unemployment.5. a. The demand for labor is determined by the amount of labor that a profit-maximizing firm wants tohire at a given real wage. The profit-maximizing condition is that the firm hire labor until themarginal product of labor equals the real wage,The marginal product of labor is found by differentiating the production function with respect tolabor (see Chapter 3 for more discussion),In order to solve for labor demand, we set the MPL equal to the real wage and solve for L:Notice that this expression has the intuitively desirable feature that increases in the real wagereduce the demand for labor.b. We assume that the 27,000 units of capital and the 1,000 units of labor are supplied inelastically (i.e., they will work at any price). In this case we know that all 1,000 units of labor and 27,000 units of capital will be used in equilibrium, so we can substitute these values into the above labor demand function and solve for W P .In equilibrium, employment will be 1,000, and multiplying this by 10 we find that the workers earn 10,000 units of output. The total output is given by the production function: Y =5K 13L 23Y =5(27,00013)(1,00023)Y =15,000.Notice that workers get two-thirds of output, which is consistent with what we know about theCobb –Douglas production function from Chapter 3.c. The real wage is now equal to 11 (10% above the equilibrium level of 10).Firms will use their labor demand function to decide how many workers to hire at the given realwage of 11 and capital stock of 27,000:So 751 workers will be hired for a total compensation of 8,261 units of output. To find the newlevel of output, plug the new value for labor and the value for capital into the production function and you will find Y = 12,393.d. The policy redistributes output from the 249 workers who become involuntarily unemployed tothe 751 workers who get paid more than before. The lucky workers benefit less than the losers lose as the total compensation to the working class falls from 10,000 to 8,261 units of output.e. This problem does focus on the analysis of two effects of the minimum-wage laws: they raise thewage for some workers while downward-sloping labor demand reduces the total number of jobs. Note, however, that if labor demand is less elastic than in this example, then the loss ofemployment may be smaller, and the change in worker income might be positive.6. a. The labor demand curve is given by the marginal product of labor schedule faced by firms. If acountry experiences a reduction in productivity, then the labor demand curve shifts to the left as in Figure 7-1. If labor becomes less productive, then at any given real wage, firms demand less labor. b. If the labor market is always in equilibrium, then, assuming a fixed labor supply, an adverseproductivity shock causes a decrease in the real wage but has no effect on employment orunemployment, as in Figure 7-2.c. If unions constrain real wages to remain unaltered, then as illustrated in Figure 7-3, employment falls to L 1 and unemployment equals L – L 1.This example shows that the effect of a productivity shock on an economy depends on the role ofunions and the response of collective bargaining to such a change.7. a. If workers are free to move between sectors, then the wage in each sector will be equal. If the wages were not equal then workers would have an incentive to move to the sector with the higher wage and this would cause the higher wage to fall, and the lower wage to rise until they were equal.b. Since there are 100 workers in total, L S = 100 – L M . We can substitute this expression into thelabor demand for services equation, and call the wage w since it is the same in both sectors:L S = 100 – L M = 100 – 4wL M = 4w.Now set this equal to the labor demand for manufacturing equation and solve for w:4w = 200 – 6ww = $20.Substitute the wage into the two labor demand equations to find L M is 80 and L S is 20.c. If the wage in manufacturing is equal to $25 then L M is equal to 50.d. There are now 50 workers employed in the service sector and the wage w S is equal to $12.50.e. The wage in manufacturing will remain at $25 and employment will remain at 50. If thereservation wage for the service sector is $15 then employment in the service sector will be 40. Therefore, 10 people are unemployed and the unemployment rate is 10 percent.8. Real wages have risen over time in both the United States and Europe, increasing the reward forworking (the substitution effect) but also making people richer, so they want to “buy” more leisure (the income effect). If the income effect dominates, then people want to work less as real wages go up. This could explain the European experience, in which hours worked per employed person have fallen over time. If the income and substitution effects approximately cancel, then this could explain the U.S.experience, in which hours worked per person have stayed about constant. Economists do not have good theories for why tastes might differ, so they disagree on whether it is reasonable to think that Europeans have a larger income effect than do Americans.9. The vacant office space problem is similar to the unemployment problem; we can apply the sameconcepts we used in analyzing unemployed labor to analyze why vacant office space exists. There is a rate of office separation: firms that occupy offices leave, either to move to different offices or because they go out of business. There is a rate of office finding: firms that need office space (either to start up or expand) find empty offices. It takes time to match firms with available space. Different types of firms require spaces with different attributes depending on what their specific needs are. Also, because demand for different goods fluctuates, there are “sectoral shifts”—changes in the composition ofdemand among industries and regions that affect the profitability and office needs of different firms.。

Principles of microeconomics2015年6月27日中国地质大学（武汉）Principles of microeconomics王美琦2015-06-27CHAPTER 5:Elasticity and its ApplicationPrinciples of microeconomics王美琦 [2015年5月]The elasticity of demand 需求弹性 The price elasticityDeterminants①Availability of close substitutes ：相近替代品的可获性Goods with close substitutes②Necessities versus luxuries ：必需品与奢侈品Necessities have inelastic demands ，luxurious have elastic demands③Definition of the market ：市场的定义Narrowly defined markets broadly defined markets④Time horizon ：时间框架 Over longer time horizonComputing①定义法：价格变动百分比需求变动百分比需求价格弹性=②中点法求弧弹性：)(21)(2112121212P P P P Q Q Q Q ----=需求价格弹性 ③点弹性： QP dP Q *d =需求价格弹性 The income elasticity 需求收入弹性 收入变动百分比需求变动百分比需求收入弹性=Normal goods positive Inferior goods negtiveThe cross-price elasticity 交叉价格弹性的价格变动的百分比物品的需求量变动百分比物品需求的交叉价格弹性21=Substitutes positive Complements negtiveThe elasticity of supply 供给弹性Determinants①Ability of sellers to change the amount of good they produce ②Time horizon ：时间框架 Computing价格变动百分比供给变动百分比供给价格弹性=Case study 供给需求弹性应用 ①农业好消息对农民的负面影响 ②OPEC 不会一直保持高油价 ③禁毒在短期长期中增加犯罪CHAPTER 6:Supply,Demand and Government PoliciesControls in prices价格控制Price ceiling价格上限Not binding非限制性价格上限>均衡价格Binding constraint限制性约束价格上限<均衡价格Case study：房屋租金、汽油价格控制Price floor价格下限Not binding非限制性价格下限<均衡价格Binding constraint限制性约束价格下限>均衡价格Case study：最低工资Evaluating price controls评价Against市场通常是组织经济活动的好方法。

微观经济学关键概念中英文对照CHAPTER 1scarcity稀缺性economics经济学efficiency效率equity平等opportunity cost机会成本rational people理性人marginal changes边际变动incentive激励market economy市场经济property rights产权market failure市场失灵externality外部性market power市场势力productivity生产率inflation通货膨胀business cycle经济周期CHAPTER 2circular-flow diagram循环流向图production possibilities frontier生产可能性边界microeconomics微观经济学macroeconomics宏观经济学positive statements实证表述normative statements规范表述CHAPTER 3absolute advantage绝对优势opportunity cost机会成本comparative advantage比较优势imports进口exports出口CHAPTER 4market市场competitive market竞争市场quantity demanded需求量law of demand需求定理demand schedule需求表demand curve需求曲线normal good正常物品inferior good低档物品substitutes替代品complements互补品quantity supplied供给量law of supply供给定理supply schedule供给表supply curve供给曲线equilibrium均衡equilibrium price均衡价格equilibrium quantity均衡数量surplus过剩shortage短缺law of supply and demand供求定理CHAPTER 5elasticity弹性price elasticity of demand需求价格弹性total revenue总收益income elasticity of demand需求收入弹性cross-price elasticity of demand需求的交叉价格弹性price elasticity of supply供给价格弹性CHAPTER 6price ceiling价格上限price floor价格下限tax incidence税收归宿CHAPTER 7welfare economics福利经济学willingness to pay支付意愿consumer surplus消费者剩余cost成本producer surplus生产者剩余efficiency效率equity平等CHAPTER 8deadweight loss无谓损失CHAPTER 9world price世界价格tariff关税CHAPTER 10externality外部性internalizing the externality外部性的内在化Coase theorem科斯定理transaction costs交易成本corrective tax矫正税CHAPTER 11Excludability排他性rivalry in consumption消费中的竞争性private goods私人物品public goods公有物品common resources公有资源free rider搭便车者cost-benefit analysis成本收益分析Tragedy of the Commons公有地悲剧CHAPTER 12CHAPTER 13total revenue总收益total cost总成本profit利润explicit costs显性成本implicit costs隐性成本economic profit经济利润accounting profit会计利润production function生产函数marginal product边际产量diminishing marginal product边际产量递减fixed costs固定成本variable costs可变成本average total cost平均总成本average fixed cost平均固定成本average variable cost平均可变成本marginal cost边际成本efficient scale有效规模economies of scale规模经济diseconomies of scale规模不经济constant returns to scale规模收益不变CHAPTER 14competitive market竞争市场average revenue平均收益marginal revenue边际收益sunk cost沉没成本CHAPTER 15Monopoly垄断企业natural monopoly自然垄断price discrimination价格歧视CHAPTER 16Oligopoly寡头monopolistic competition垄断竞争collusion勾结cartel卡特尔Nash equilibrium纳什均衡game theory博弈论prisoners＇dilemma囚徒困境dominant strategy占优策略CHAPTER 17monopolistic competition垄断竞争CHAPTER 18factors of production生产要素production function生产函数marginal product of labor劳动的边际产量diminishing marginal product边际产量递减value of the marginal product边际产量值capital资本CHAPTER 19compensating differential补偿性工资差别human capital人力资本union工会strike罢工efficiency wages效率工资discrimination歧视CHAPTER 20poverty rate贫困率poverty line贫困线in-kind transfers实物转移支付life cycle生命周期permanent income持久收入utilitarianism功利主义utility效用liberalism自由主义maximin criterion最大化标准social insurance社会保障libertarianism自由意志主义welfare福利negative income负所得税。

Microeconomics, 4e (Perloff)Chapter 7 Costs7.1 Measuring Costs1) Economic costs of an input includeA) only implicit costs.B) only explicit costs.C) both implicit and explicit costs.D) whatever management wishes to report to the shareholders.Answer: CTopic: Measuring Costs2) The cost of waiting two months for health care to address a debilitating problem in Canada is most accurately described asA) an explicit cost.B) an accounting cost.C) no real cost.D) an opportunity cost.Answer: DTopic: Measuring Costs3) Sarah earns $40,000 per year working for a large corporation. She is thinking of quitting this job to work full time in her own business. She will invest her savings of $50,000 (which currently has an annual 10% rate of return) into the business. Her annual opportunity cost of this new business isA) $0.B) $40,000.C) $45,000.D) $90,000.Answer: CTopic: Measuring Costs4) The Nifty Gum Co. has purchased a large parcel of land for $1 million. The company recently discovered that the land is contaminated and is worthless to all possible buyers. The opportunity cost of the land isA) $0.B) $1 million.C) some amount greater than $0 but less than $1 million.D) equal to the cost of the factory that was planned to be built there.Answer: ATopic: Measuring Costs5) Johnny has worked as a CPA for five years and wants to open his own public accounting practice. The cost of his college degree in accounting representsA) the opportunity cost of this endeavor.B) a sunk cost.C) an expense.D) a variable cost.Answer: BTopic: Measuring Costs6) Economists proclaim that competitive firms make zero economic profit in the long run. This shows howA) detached economists are from the real world.B) unrealistic economic theory is.C) firms cover all their cost, both monetary and non-monetary.D) firms cover only monetary cost when economic profits are zero.Answer: CTopic: Measuring Costs7) If a firm buys a building so as to have office space for its workers, the monthly opportunity cost of the building is best measured asA) the monthly mortgage payment the firm must pay.B) the price the firm paid divided by twelve.C) zero.D) the rent the firm could earn if it rented the building to another firm.Answer: DTopic: Measuring CostsFor the following, please answer "True" or "False" and explain why.8) When buying a piece of equipment, it is always best for the firm to pay cash instead of borrowing the funds since this renders the equipment less costly.Answer: False. It depends. The opportunity cost of the capital when paying cash is the interest the firm receives on its cash reserves. This is an implicit cost. The opportunity cost of the capital when the funds are borrowed is the interest the firm must pay to the lender. This is an explicit cost. If the rate the firm receives on its cash reserves exceeds the rate at which it borrows, the firm is better off borrowing the funds to buy the equipment.Topic: Measuring Costs9) Four years after graduating from college you must decide if you want to go on as an accountant (your college major) or if you want to make a career change and become a singer. The cost of your education will matter for your decision.Answer: False. At this point the cost of your education represents a sunk cost and therefore should not figure into your decision. You incur it no matter what decision you make.Topic: Measuring Costs10) An accountant may amortize the expense of a durable good by dividing the total amount spent on the good by the number of years the good is expected to last. An economist may amortize the expense of a durable and never fully account for the total expense.Answer: True. The accountant uses a set of predetermined rules to amortize the total expense of the good. The economist amortizes based on the opportunity cost of the good, which may never sum to the total expense of the good.Topic: Measuring Costs11) Your company makes copper pipes. Over the years, you have collected a large inventory of raw copper. The production process involves melting the copper and shaping it into pipes. You also have a large stockpile of pennies. Suppose the price of copper rises so much that the copper in the penny becomes worth more than one cent. Should you melt down your pennies?Answer: This problem appeared as a puzzle in the Journal of Economic Perspectives (Winter, 1988). It is true (in this problem) that the pennies when melted currently have a value greater than one cent. Yet, the price of copper can fluctuate. If the price of copper stays high, it does not matter if you melt pennies or not. However, if the price of copper falls so that the value of the copper in the penny falls below one cent, your unmelted pennies are still worth one cent. Your melted pennies would be worth less than one cent. Thus, as long as you have some other source of copper, you are better off melting that copper and not the pennies.Topic: Measuring Costs12) You have two career options. You can work for someone else for $50,000 a year, or, you can run your own business, with an annual revenue of $100,000, and explicit costs of $40,000 annually. Explain which career option a profit-maximizer would select and why.Answer: In the absence of other implicit costs a profit-maximizer will run their own business. The business owner will receive $100,000 - $40,000 = $60,000. The opportunity cost is only $50,000.Topic: Measuring Costs7.2 Short-Run Costs1) A firm's marginal cost can always be thought of as the change in total cost ifA) the firm produces one more unit of output.B) the firm buys one more unit of capital.C) the firm's average cost increases by $1.D) the firm moves to the next highest isoquant.Answer: ATopic: Short-run Costs2) Fixed costs areA) a production expense that does not vary with output.B) a production expense that changes with the quantity of output produced.C) equal to total cost divided by the units of output produced.D) the amount by which a firm's cost changes if the firm produces one more unit of output.Answer: ATopic: Short-run Costs3) Variable costs areA) a production expense that does not vary with output.B) a production expense that changes with the quantity of output produced.C) equal to total cost divided by the units of output produced.D) the amount by which a firm's cost changes if the firm produces one more unit of output.Answer: BTopic: Short-run Costs4) Which of the following statements is NOT true?A) AC = AFC + AVCB) C = F + VCC) AVC = wage/MP LD) AFC = AC - AVCAnswer: CTopic: Short-run Costs5) Joey's Lawncutting Service rents office space from Joey's dad for $300 per month. Joey's dad is thinking of increasing the rent to $400 per month. As a result Joey's marginal cost of cutting grass willA) increase by $100 divided by the amount of grass cut.B) increase by $100.C) decrease by $100.D) not change.Answer: DTopic: Short-run Costs6) Suppose a firm can only vary the quantity of labor hired in the short run. An increase in the cost of capital willA) increase the firm's marginal cost.B) decrease the firm's marginal cost.C) have no effect on the firm's marginal cost.D) More information is needed to answer the question.Answer: CTopic: Short-run Costs7) Suppose the total cost of producing T-shirts can be represented as TC = 50 + 2q. The marginal cost of the 5th T-shirt isA) 2.B) 10.C) 12.D) 60.Answer: ATopic: Short-run Costs8) Suppose the total cost of producing T-shirts can be represented as TC = 50 + 2q. The average cost of the 5th T-shirt isA) 2.B) 12.C) 52.D) 60.Answer: BTopic: Short-run Costs9) Suppose the total cost of producing T-shirts can be represented as TC = 50 + 2q. Which of the following statements is TRUE at all levels of production?A) MC = AVCB) MC = ACC) MC > AFCD) All of the above.Answer: ATopic: Short-run Costs10) Suppose the short-run production function is q = 10 * L. If the wage rate is $10 per unit of labor, then AVC equalsA) q.B) q/10.C) 10/q.D) 1.Answer: DTopic: Short-run Costs11) Suppose the short-run production function is q = 10 * L. If the wage rate is $10 per unit of labor, then MC equalsA) q.B) q/10.C) 10/q.D) 1.Answer: DTopic: Short-run Costs12) If average cost is decreasingA) Marginal cost equals average cost.B) Marginal cost exceeds average cost.C) Marginal cost is less average cost.D) Not enough informationAnswer: CTopic: Short-run Costs13) If average cost is positiveA) Marginal cost equals average cost.B) Marginal cost exceeds average cost.C) Marginal cost is less average cost.D) Not enough informationAnswer: DTopic: Short-run Costs14) Suppose the short-run production function is q = L0.5. If the marginal cost of producing the tenth unit is $5, what is the wage per unit of labor?A) $1B) $0.5C) $0.25D) It cannot be determined without more information.Answer: CTopic: Short-run Costs15) Suppose the short-run production function is q = 10 * L. If the wage rate is $10 per unit of labor, then AFC equalsA) 0.B) 1.C) 10/q.D) It cannot be determined from the information provided.Answer: DTopic: Short-run Costs16) When a firm produces one unit, the variable cost is $3. When the firm produces two units, the variable cost is $6. What is the marginal cost associated with two units of production?A) $2B) $0.5C) $6D) $3Answer: DTopic: Short-run Costs17) In the short run, the point at which diminishing marginal returns to labor begin is the point at which the marginal cost curveA) peaks.B) bottoms out.C) is upward sloping.D) is downward sloping.Answer: BTopic: Short-run Costs18) If the marginal cost of producing a good is increasing as a firm produces more of the good, then which of the following must be TRUE?A) AFC is rising.B) AVC is rising.C) MC > AVC.D) MPL is falling.Answer: DTopic: Short-run Costs19) If the average cost of producing a good is increasing as a firm produces more of the good, then which of the following must be TRUE?A) AFC is falling.B) AVC is rising.C) MC > AVC.D) All of the above.Answer: DTopic: Short-run Costs20) If a particular production process is subject to diminishing marginal returns to labor at every level of output, then at every level of outputA) AC is upward sloping.B) MC exceeds AVC.C) AFC is constant.D) All of the above.Answer: BTopic: Short-run Costs21) Marginal Cost is equal toA) the increase in total cost from increasing the amount of labor by one unit.B) the increase in average cost from increasing the amount of labor by one unit.C) Both A and B.D) Neither A nor B.Answer: CTopic: Short-run Costs22) Suppose each worker must use only one shovel to dig a trench, and shovels are useless by themselves. In the short run, an increase in the price of shovels will result inA) fewer shovels being purchased.B) more workers being hired.C) a decrease in the firm's output.D) no change in the firm's output.Answer: DTopic: Short-run Costs23) Which of the following will cause the marginal cost curve of making cigarettes to shift?A) A $5 million penalty charged to each cigarette maker.B) A $1 per pack tax on cigarettes.C) A $1 million advertising campaign by the American Cancer Society.D) All of the above.Answer: BTopic: Short-run Costs24) Which of the following will cause the average cost curve of making cigarettes to shift?A) A $5 million penalty charged to each cigarette maker.B) A $1 per pack tax on cigarettes.C) A $1 an hour wage increase paid to all cigarette production workers.D) All of the above.Answer: DTopic: Short-run Costs25) Which of the following will cause the average fixed cost curve of making cigarettes to shift?A) A $5 million penalty charged to each cigarette maker.B) A $1 per pack tax on cigarettes.C) A $3 per hour wage increase.D) An increase in the demand for cigarettes.Answer: ATopic: Short-run Costs26) A specific tax of $1 per unit of output will affect a firm'sA) average total cost, average variable cost, average fixed cost, and marginal cost.B) average total cost, average variable cost, and average fixed cost.C) average total cost, average variable cost, and marginal cost.D) marginal cost only.Answer: CTopic: Short-run CostsFor the following, please answer "True" or "False" and explain why.27) The "Law of Diminishing Marginal Returns" could also be termed the "Law of Increasing Marginal Costs."Answer: True. Since MC = w/MP L in the short run, the fact that MPL eventually declines means that MC must eventually increase.Topic: Short-run Costs28) The marginal cost curve intersects the average fixed cost curve at its minimum.Answer: False. Marginal cost intersects average variable cost (and average cost) at its minimum.Topic: Short-run Costs29) A consumer purchases a book by driving across town to a bookstore, standing in line for five minutes to pay the cashier, and then pays $5. The same book is purchased by another consumer who spends 2 minutes placing the order over the internet for $10. The book necessarily cost the first consumer less.Answer: False. The opportunity cost of driving across town and standing in line may have raised the total cost of the book to the first consumer to more than $10.Topic: Short-run Costs30) A firm's production function for pretzels is shown in the above figure. If the firm's fixed cost equals $100 per time period and the wage rate equals $1 per unit of labor per time period, calculate the firm's MC, AVC, and AC schedules. Do these cost functions follow the general rules concerning the relationships between MC, AVC and AC?Answer:❑✌☞ ✌✞✌ MC > AVC, AVC is rising.MC < AC, AC is falling.Topic: Short-run Costs31) Explain why the marginal cost curve intersects a U-shaped average cost curve at its minimum point. Answer: At low quantities, the average cost curve declines as the quantity increases. The marginal cost is below the average cost. The marginal cost represents the cost of an additional unit of production. Thus, as the marginal cost curve declines, this pulls the average cost down from its previous level. Then, the marginal cost curve will begin to rise. However, the marginal cost is still below the average cost, which will continue to lower the average cost. When the two costs are equal the marginal cost will leave the average cost unchanged. Then, the marginal cost will be above the average cost so it will start to pull up the average cost. Thus, the marginal cost curve will intersect the average cost curve at its minimum point.Topic: Short-run Costs7.3 Long-Run Costs1) In the long run, fixed costs areA) sunk.B) avoidable.C) larger than in the short run.D) not included in production decisions.Answer: BTopic: Long-run Costs2) The slope of the isocost line tells the firm how muchA) capital must be reduced to keep total cost constant when hiring one more unit of labor.B) capital must be increased to keep total cost constant when hiring one more unit of labor.C) more expensive a unit of capital costs relative a unit of labor.D) the isocost curve will shift outward if the firm wishes to produce more.Answer: ATopic: Long-run Costs3) Which of the following does NOT represent a possible shape of the long-run average cost curve?A) downward-slopingB) upward-slopingC) U-shapedD) verticalAnswer: DTopic: Long-run Costs4) The slope of the isoquant tells the firm how muchA) output increases when labor increases by one unit.B) output increases when capital and labor are doubled.C) capital must decrease to keep output constant when labor increases by one unit.D) a unit of capital costs relative to the cost of labor.Answer: CTopic: Long-run Costs5) If an isocost line crosses the isoquant twice, a cost minimizing firm willA) use a different isocost line to select the bundle of inputs.B) use the input bundle associated with the intersection on the higher point of the isoquant.C) use the input bundle associated with the intersection on the lower point of the isoquant.D) Both B and C.Answer: ATopic: Long-run Costs6) When the isocost line is tangent to the isoquant, thenA) MRTS = w/r.B) the firm is producing that level of output at minimum cost.C) the last dollar spent on capital yields as much extra output as the last dollar spent on labor.D) All of the above.Answer: DTopic: Long-run Costs7) A firm can minimize cost byA) picking the bundle of inputs where the lowest isocost line touches the isoquant.B) picking the bundle of inputs where the isoquant is tangent to the isocost line.C) picking the bundle of inputs where the last dollar spent on one input gives as much extra output as the last dollar spent on any other input.D) All of the above.Answer: DTopic: Long-run Costs8) When the isocost line is tangent to the isoquant, thenA) MPL = MPK.B) the firm is producing that level of output at minimum cost.C) the firm has achieved the right economies of scale.D) All of the above.Answer: BTopic: Long-run Costs9) If the wage in increases the isocost line willA) stay the same.B) shift outward in parallel fashion.C) rotate inward around the point where only capital is employed in production.D) shift inward in parallel fashion.Answer: CTopic: Long-run Costs10) If the isoquants are straight lines or L-shaped, then a cost-minimizing firm willA) not be able to minimize costs.B) find the lowest isocost line touching the relevant isoquant.C) find the highest isocost line touching the relevant isoquant.D) choose not to produce any output.Answer: BTopic: Long-run Costs11) If the marginal rate of technical substitution for a cost minimizing firm is 10, and the wage rate for labor is $5, what is the rental rate for capital in dollars?A) .5B) 1C) 2D) 10Answer: ATopic: Long-run Costs12) Suppose MPL = 0.5 * (q/L) and MPK = 0.5 * (q/K). In the long run, the firm will hire equal amounts of capital and laborA) all of the time.B) only when w = r.C) only when w = 0.5 * r.D) at no point in time.Answer: BTopic: Long-run Costs13) Suppose that each worker must use only one shovel to dig a trench, and shovels are useless by themselves. In the long run, an increase in the price of shovels will result inA) fewer shovels being purchased to produce the same number of trenches.B) more workers being hired to produce the same number of trenches.C) the firm wishing to produce more trenches.D) no change in the firm's input mix.Answer: DTopic: Long-run Costs14) Suppose that each worker must use only one shovel to dig a trench, and shovels are useless by themselves. In the long run, the firm will experienceA) increasing returns to scale.B) constant returns to scale.C) decreasing returns to scale.D) The returns to scale cannot be determined from the information provided.Answer: BTopic: Long-run Costs15) Suppose that each worker must use only one shovel to dig a trench, and shovels are useless by themselves. In the long run, the firm's cost function isA) TC = (w/r) * q.B) TC = (w + r)/q.C) TC = (w + r).D) TC = (w + r) * q.Answer: DTopic: Long-run Costs16) At the XYZ Co., a unit of capital costs 3 times as much as a unit of labor. If the isoquants are convex, and the firm does not change its input mix in the long run, we can conclude thatA) MPK = 3 * MP L.B) the firm will not hire any capital.C) the firm will hire 3 times as much labor as capital.D) the firm will hire 3 times as much capital as labor.Answer: ATopic: Long-run Costs17) The production of cigarettes is highly automated; however, a worker is required to monitor each machine. Machines and workers do not interact with one another. Given this information, there are most likelyA) economies of scale.B) economies of scope.C) constant returns to scale.D) increasing returns to scale.Answer: CTopic: Long-run Costs18) Suppose that capital and labor must be kept in a fixed proportion to produce a particular good. For example, digging a trench requires one worker who has one shovel. What does this imply about returns to scale?A) There are constant returns to scale.B) There are increasing returns to scale.C) There are decreasing returns to scale.D) Nothing.Answer: ATopic: Long-run Costs19) A change in relative factor prices will always result inA) a change in the slope of the isoquants.B) a tangency between the new isocost line and a new isoquant.C) a rotation of the isocost lines.D) All of the above.Answer: CTopic: Long-run Costs20) Assuming that w and r are both positive, if the long-run expansion path is horizontal, thenA) MP K = 0.B) MRTS is a function of capital only.C) w = r.D) All of the above.Answer: BTopic: Long-run Costs21) The above figure shows the long-run expansion path. The long-run average cost curve will beA) horizontal.B) downward sloping.C) upward sloping.D) vertical.Answer: BTopic: Long-run Costs22) The long run average cost curve may initially slope downward due toA) decreasing average fixed costs.B) increasing marginal returns.C) economies of scale.D) All of the above.Answer: CTopic: Long-run Costs23) If a production function is represented as q = LαKβ, the long-run average cost curve will be horizontal as long asA) a + b = 0.B) a + b = 1.C) q > 0.D) L = K.Answer: BTopic: Long-run Costs24) If there are diseconomies of scale within a given range of output, which of following is(are) TRUE?A) The short-run average cost curve must be upward sloping within that range of output.B) The long-run average cost curve must be upward sloping within that range of output.C) Long-run average cost must equal short-run average cost.D) All of the above.Answer: BTopic: Long-run Costs25) The total cost of producing one unit is $50. The total cost of producing two units is $75. At a production level of two units, the cost function exhibitsA) economies of scale.B) rising average costs.C) increasing marginal costs.D) constant returns to scale.Answer: ATopic: Long-run CostsFor the following, please answer "True" or "False" and explain why.26) If increasing returns to scale are present, the long-run average cost increases as more output is produced. Answer: False. Increasing returns to scale imply that with a doubling of inputs, output more than doubles. Since average cost is the ratio of total cost divided by output, this increase in inputs will cause the numerator to be just double the old value while the new denominator is more than double the old value. As a result, long-run average cost falls as more output is produced.Topic: Long-run Costs27) Economies of scale and Increasing Returns to Scale are the same thing looked at from either the production or cost perspective.Answer: False. Increasing returns to scale imply economies of scale but the reverse is not true. A firm can experience economies of scale for other reasons (without increasing returns to scale)Topic: Long-run Costs28) Explain the difference between fixed costs in the short run and fixed costs in the long run.Answer: In the short run fixed costs are sunk; in the long run, fixed costs are avoidable.Topic: Long-run Costs29) What are the functions for MC and AC if TC = 100q + 100q2? Are the returns to scale increasing, decreasing, or constant?Answer: MC = 100 + 200qAC = 100 + 100qSince AC increases with an increase in output, there are decreasing returns to scale.Topic: Long-run Costs30) Explain how a firm can have constant returns to scale in production and economies of scale in cost. Answer: A firm can have constant returns to scale in production at every output level. If the firm doubled all inputs the output would double. However, the firm may have a decreasing average cost. As more inputs areused and output increases, the average cost declines, which is known as economies of scale.Topic: Long-run Costs31) Explain why the long-run total cost curve, not the short-run total cost curve, shows the lowest cost of producing any level of output. Is there an exception?Answer: In the long run, all costs are variable so the firm can select the least-cost mix of all inputs to produce any given quantity. The exception would be at minimum long-run cost where min. LR and min. SR costs are equal.Topic: Long-run Costs32) A local non-profit group prints a weekly newsletter. Professional typists earn $10 per hour and can type 2 pages per hour. Unpaid volunteers can type only 1 page per hour. Measuring hours of professional typist services on the vertical axis and hours of unpaid volunteer typist services on the horizontal axis, draw the relevant isoquant and isocost curves if the newsletter is 10 pages long. What input mix is chosen by the non-profit group if they wish to minimize the cost of the newsletter? If the group will reimburse volunteers for expenses (lunch, driving), how much must the reimbursement be for your answer to change? Answer:See the above figure. The isoquant is a straight line with a slope of 1/2. The group can use either 5 pros, 10 volunteers, or some combination of the two. The isocost curves are horizontal since volunteers are free. As a result, the lowest isocost curve is achieved by hiring all volunteers. If the group reimbursed volunteers for expenses (lunch, driving, etc.) then the group will still hire all volunteers as long as they do not cost more than $5 per hour.Topic: Long-run Costs33) A firm pays $5 for each unit of capital. Labor costs $5 per hour for the first 10 hours and $10 per hour for every hour thereafter. Draw the isocost curves for total costs of $50 and $100.Answer:See the above figure.Topic: Long-run Costs34) To dig a trench, each worker needs a shovel. Workers can use only one shovel at a time. Workers without shovels do nothing, and shovels cannot operate on their own. Graphically determine the number of shovels and workers used by a firm to dig 2 trenches when:(a) w = 10 and r = 10(b) w = 10 and r = 5Answer:See the above figure. Because the production process requires fixed proportions of K and L, the firm cannot change input mix when the relative factor costs change.Topic: Long-run Costs35) Suppose the production function is q = 12 L0.25K0.75. Determine the long-run capital-to-labor ratio (K/L) if the cost a unit of capital (r) is three times the cost of a unit of labor (w).Answer: The firm minimizes costs by setting MRTS = w/r. MRTS = MP L/MP K = K/3L = 1/3 = w/r. This firm will set K/L equal to one.Topic: Long-run Costs36) "If the wage rate paid to one form of labor is twice the cost of another form of labor, the first type of labor must be twice as productive." Comment.Answer: This is true. Firms minimize cost by setting the ratio of marginal productivity per unit cost equally across all inputs. If one form of labor is twice as expensive as another, the firm will want the MP of the first type of labor to be twice that of the second.Topic: Long-run Costs。

Name：__________________________ Date：_____________1。

The Solow growth model describes:A）how output is determined at a point in time。

B）how output is determined with fixed amounts of capital and labor。

C)how saving， population growth, and technological change affectoutput over time.D)the static allocation， production, and distribution of theeconomy's output。

2。

Unlike the long—run classical model in Chapter 3, the Solow growth model：A)assumes that the factors of production and technology are thesources of the economy's output.B）describes changes in the economy over time.C)is static。

D)assumes that the supply of goods determines how much output isproduced。

3.In the Solow growth model, the assumption of constant returns to scalemeans that:A)all economies have the same amount of capital per worker.B)the steady—state level of output is constant regardless of thenumber of workers。