經濟學原理i10秋季期中

期中考試2（A卷答案）注意：請將所有題目的答案寫在答題冊上，寫在本試題紙上一律無效。一、判斷題（判斷并簡要說明理由，必要時可以用圖形。每題4分，共20分AstateoftheU.S.raisesitssalestaxfrom5percentto6percent.Thestaterevenuecommissionerforecastsa20percentincreaseinsalestaxrevenue.Thisforecastiscorrect.得銷售入增加小于20％。Consideracountryimportsagoodfromabroad.Ifdemandisperfectlyinelastic,consumersdonotbenefitfromtradeandthereareonlylossesfromtrade.(Useadiagram)False.Consumerswillenjoyalowerprice(butnotmoretydemanded)andwillbenefitfromtrade.Benefitstoconsumersareevenlargerthanlossestoproducers,sotherearestillgainsfromtrade(shadedareainthediagrambelow).Coasianbargaining（談判）cansolveproblemswithnegativeexternalities,butnotproblemswithpositiveexternalities.TheWashingtonD.C.Metro(subway)systemchargeshigherfaresduringrushhourthanduringtherestoftheday.Theonlyreasonforthisisthatdemandforsubwayridesduringrushhourishigherthandemandduringtherestoftheday.False.Higherdemandisonepossiblereason.Butthereisstillanother:Whenthesystemiscongested,eachadditionalriderimposescostsonotherriders.Increasingthefareduringrushhourinternalizesthisnegativeexternality.Ifgoodscanbegotforfree,thenneitheritsproducingnoritsusingcangenerate False.Agoodbeinggotforfreedoesnotmeanthatitsproducingandusingdoesnothavesocialcost.Infact,withoutapricetoreflectitssocialbenefitsandcosts,itsproducingandusingisoften二、選擇題（每題3分，共36分。每題只有一個正確答案。在東門外一家面館里，一碗牛肉面售價為16.8元，一份小菜售價為4元。如果點“牛肉面加小菜”套餐則只需要18.5元。對此，常去那里吃飯的學生發(fā)SupposethedemandforFrenchbreadrisesbecauseofitsbettertastes.ThentheconsumersurplusinthemarketforFrenchbreadwill ,producersurpluswill .Theproducersurplusinthemarketforflourwill ,consumersurplus(ormoreprecisely,netbenefitsofbuyers)will increase,increase,increase,increaseordecrease,increase,increase,increaseorincrease,increase,increase,increaseordecrease,increase,increase,EconomiststendtoseeticketscalawayforafewtoprofitwithoutproducinganythingofaninequitableinterferenceintheorderlyprocessofticketawayofincreasingtheefficiencyofticketanunproductiveactivitywhichshouldbemadeillegalBillGatesbecameoneoftherichestpeopleintheworldbysellingWindowsthroughouttheworld.Whatkindofbenefitsofinternationaltradecanthisfactbestillustrate?IncreasedvarietyofLowercoststhrougheconomiesofIncreasedEnhancedflowofIfCanadaweretosubsidizetheproductionofwoolblankets,andsellthemintheU.S.atartificiallylowprices,theU.S.economywouldbe ,theCanadaeconomywould ,andtheU.S.andCanadaeconomyasawholewouldbe worseoff,betteroff,worseofforbetterbetteroff,worseoff,worseofforbetterbetteroff,betteroff,betterbetteroff,worseoff,worseTheU.S.ernmenthasattimespressuredJapanto“voluntarily”limitthesaleofJapanesecarsintheUnitedStates.ComparedwithatariffwhichachievesthesamenumberofcarsimportedfromJapan，thisvoluntarylimitationpolicywillmaketheU.S.consumers theU.S.producers ;theU.S.ernment ;andtheU.S.asawhole worseoff;worseoff;worseoff;worsebetteroff;worseoff;unaffected;betterunaffected;unaffected;worseoff;worse以下理由中，不能斯談判。則對于吸煙者而言，第種規(guī)定最有利，第種規(guī)定最不利。Fourroommatesareplanningtospendtheweekendintheirdormroomwatchingoldmovies,andtheyaredebatinghowmanytowatch.Hereistheirwillingnesstopayforeachfilm:First7542Second6431Third53104210Fifth3100Withinthedormroom,theshowingofamovieisapublicgood.Itcosts$8torentaConsiderthefollowingsituations.(a)AlltheroommatesdecidehowmanymoviestorentthroughCoasianbargaining.(b)Eachroommatedecidesindependentlyhowmanymoviestorent.(c)Alltheroommatesagreeinadvancetosplitequallythecostofrenting,andtheyuseamajorityruletodecidehowmanymoviestorent(i.e.,ifmorethanhalfofthemagreeanumberofmovies,thatnumberofmovieswillberent).Amongallthesituations,situationwillinducethehighestnumberofmovies,andsituation willinducethelowestnumberofmovies.(a),(a)and(c),(a),(b),Thedemandforfoodisrelativelyinelastic.Comparedwithothergoods,taxingfoodcanraisemoretaxrevenue,causelessdeadweightlossandimprovevertical-raisemoretaxrevenue,causelessdeadweightlossandworsenvertical-raisemoretaxrevenue,causemoredeadweightlossandworsenvertical-raiselesstaxrevenue,causemoredeadweightlossandimprovevertical-equity三、問答題（3小題，41分PublicPoliciestowardExternalities(10ThePristineRiverhastwopollutingfirmsonitsbanks.AcmeIndustrialandCreativeChemicalseachdump100tonsofglopintotherivereachyear.Thecostofreducingglopemissionspertonequals$10forAcmeand$100forCreative.Thelocalernmentwantstoreduceoverallpollutionfrom200tonsto50tons.Iftheernmentknowsthecostofreductionforeachfirm,whatreductionswillitimposetoreachitsoverallgoal?Whatwillbethecosttoeachfirmandthetotalcosttothefirmstogether？(2points)Iftheernmentknewthecostofreductionateachfirm,itwouldhaveAcmeeliminateallitspollution(atacostof$10pertontimes100tons=$1,000)andhaveCreativeeliminatehalfofitspollution(atacostof$100pertontimes50tons=$5,000).Thisminimizesthetotalcost($6,000)ofreducingthepollutionto50tons.Inamoretypicalsituation,theernmentdoesnotknowthecostofpollutionreductionforeachfirm.Iftheernmentdecidestoreachitsoverallgoalbyimposinguniformreductionsonthefirms,calculatethecosttoeachfirm,andthetotalcosttothefirmstogether.(2points)Ifeachfirmhadtoreducepollutionto25tons(soeachhadtoreducepollutionby75tons),thecosttoAcmewouldbe75x$10=$750andthecosttoCreativewouldbe75x$100=$7,500.Thetotalcostwouldbe$8,250.Nowsupposetheernmentgiveseachfirm25tonsoftradablepollutionpermits.Whosellspermitsandhowmanydoesitsell?Whatwouldbethepriceofpermits?Whatisthetotalcostofreductiontothefirmstogetherinthissituation?Doyoupreferpolicyinpart(b)orinthispart?(3points)Acmewillsellallofitspermitsatapricebetween$10and$100.Asaresult,AcmewillreduceitspollutiontozeroandCreativewillreduceitspollutionto50tons.Thusthetotalcostofreductiontothefirmsis100*$10+50*$100=$6,000.Wewouldpreferpolicyinthispart,becauseitreducesthesameamountofpollutionwithsmallertotalcost.Nowsupposetheernmentcouldnotdecidehowmuchpollutionissociallydesirable,butitknowsthateachtonofglopdumpedimposesasocialcostof$50.Whatshouldtheernmentdonow?Undersucha ernmentpolicy,howmuchpollutionwouldbereducedaltogether?Whatisthetotalcostofreductioninthissituation?Doyouthinkthecostminimizedforreducingthattotalamountofpollution?Explain.(3Theernmentshouldimposeacorrectivetaxof$50foreachtonofglopdumped.ThenAcmewillreduceitspollutiontozeroandCreativewillnotreducepollutionatall.Sothetotalamountofpollutionreductionis100tons.Thetotalcostofreductionis100*$10=$1,000.Thecostisindeedminimized,becauseauniformcorrectivetaximposedforeachfirmwillhavefirmswithlowerreductioncosttoreducepollutionandviceversa.Sothetotalcostisminimized.出口退稅（13分畫出一國出口某種產品的典型的市場供求圖形（1分。Q現(xiàn)在考慮對出口企業(yè)所有產品都征稅。在圖形中表示這一政策的影響。由于該政策，國內企業(yè)的生產量如何變動，國內消費者的消費量如何變動？出口量如何變動？國內生產者福利如何變動？消費者福利如何變動？的福利如何圖形并輔助文字說明。（4分）出口量下降，從線段CD縮短到CD’。生產者福利下降，從面積BDF減少到面積BD’F’。增加，從零增加到面積F’D’GF該國從國際貿易中獲益減少，從面積CDE減少到面積CD’E’。AABCDGFEQ（不？的福利如何變動？（注：所結都與有何政策比較（4分）出口量增加，從線段CD延長到C’D。增加，從零增加到面積AA’C’G’。CDEFQ響你的回答？（4分）錯誤。出口企業(yè)的出口量比無稅時增加了。出口量從線段CD增加到C’D（直觀解釋：此時國內消費者因負擔減少了消費量，國內生產者面對世界價格不變，因而產量不變，則出口增加。）（1分）錯誤（或不一定。無謂損失從面積D’GD變?yōu)镃’G’C。兩個面積的大小