经济学资料（英文版）经济学课本答案chapter3 7页

ProblemsandApplications2.a.1・Inthetextexampleofthefarmerandtherancher,thefarmer'sopportunitycostofproducingonepoundofmeatistwopoundsofpotatoesbecauseforevery20hoursofwork,hecanproduceonepoundofmeatortwopoundsofpotatoes・Withlimitedtimeathisdisposal,producingapoundofmeatmeanshegivesuptheopportunitytoproducetwopoundsofpotatoes.Similarly,therancher'sopportunitycostofproducingonepoundofmeatis1/8poundofpotatoesbecauseforeveryhourofwork,shecanproduceonepoundofmeator1/8poundofpotatoes・Withlimitedtimeatherdisposal,producingapoundofmeatmeansshegivesuptheopportunitytoproduce1/8poundofpotatoes・SeeFigureIfMariaspendsallfivehoursstudyingeconomics,shecanread100pages,sothatistheverticalinterceptoftheproductionpossibilitiesfrontier.Ifshespendsallfivehoursstudyingsociology,shecanread250pages,sothatisthehorizontalintercept.Thetimecostsareconstant,sotheproductionpossibilitiesfrontierisastraightline.so)MedS.2IUOUOOU1100250SociologyPagesFigure3-2b・IttakesMariatwohourstoread100pagesofsociology.Inthattime,shecouldread40pagesofeconomics・Sotheopportunitycostof100pagesofsociologyis40pagesofeconomics.a.3.\nWorkersneededtomake:OneCarOneTonofGrainU.S.1/41/10Japan1/41/5b.SeeFigure3-3.With100millionworkersandfourcarsperworker,ifeithereconomyweredevotedcompletelytocars,itcouldmake400millioncars・SinceaU.S.workercanproduce10tonsofgrain,iftheU.S.producedonlygrainitwouldproduce1,000milliontons・SinceaJapaneseworkercanproduce5tonsofgrain,ifJapanproducedonlygrainitwouldproduce500milliontons.Thesearetheinterceptsoftheproductionpossibilitiesfrontiersshowninthefigure・Notethatsincethetradeoffbetweencarsandgrainisconstant,theproductionpossibilitiesfrontierisastraightline.400Grain(millionsoftons)Figure3-3c.SinceaU.S.workerproduceseither4carsor10tonsofgrain,theopportunitycostof1caris214tonsofgrain,whichis10dividedby4.SinceaJapaneseworkerproduceseither4carsor5tonsofgrain,theopportunitycostof1caris11/4tonsofgrain,whichis5dividedby4.Similarly,theU.S.opportunitycostof1tonofgrainis2/5cars(4dividedby10)andtheJapaneseopportunitycostof1tonofgrainis4/5cars(4dividedby5).Thisgivesthefollowingtable:OpportunityCostof:\n1Car(intermsoftonsofgraingivenup)1TonofGrain(intermsofcarsgivenup)U.S.21/22/5Japan11/44/5d.Neithercountryhasanabsoluteadvantageinproducingcars,sincethey'reequallyproductive(thesameoutputperworker);theU.S.hasanabsoluteadvantageinproducinggrain,sinceit'smoreproductive(greateroutputperworker).e.Japanhasacomparativeadvantageinproducingcars,sinceithasaloweropportunitycostintermsofgraingivenup.TheU.S.hasacomparativeadvantageinproducinggrain，sinceithasaloweropportunitycostintermsofcarsgivenup.f.Withhalftheworkersineachcountryproducingeachofthegoods,theU・S・wouldproduce200millioncars(thats50millionworkerstimes4carseach)and500milliontonsofgrain(50millionworkerstimes10tonseach).Japanwouldproduce200millioncars(50millionworkerstimes4carseach)and250milliontonsofgrain(50millionworkerstimes5tonseach).g.Fromanysituationwithnotrade,inwhicheachcountryisproducingsomecarsandsomegrain,supposetheU.S.changed1workerfromproducingcarstoproducinggrain.Thatworkerwouldproduce4fewercarsand10additionaltonsofgrain.ThensupposetheUSofferstotrade7tonsofgraintoJapanfor4cars・TheU.S.willdothisbecauseitvalues4carsat10tonsofgrain,soitwillbebetteroffifthetradegoesthrough.SupposeJapanchanges1workerfromproducinggraintoproducingcars・Thatworkerwouldproduce4morecarsand5fewertonsofgrain.Japanwilltakethetradebecauseitvalues4carsat5tonsofgrain,soitwillbebetteroff.Withthetradeandthechangeof1workerinboththeU.S.andJapan,eachcountrygetsthesameamountofcarsasbeforeandbothgetadditionaltonsofgrain(3fortheU.S.and2forJapan)・Thusbytradingandchangingtheirproduction,bothcountriesarebetteroff.4.a.Pafsopportunitycostofmakingapizzais1/2gallonofrootbeer,sinceshecouldbrew1/2galloninthetime(2hours)ittakeshertomakeapizza・Pathasanabsoluteadvantageinmakingpizzasinceshecanmakeoneintwohours,whileittakesKrisfourhours.Kris'sopportunitycostofmakingapizzais2/3gallonsofrootbeer,sinceshecouldbrew2/3ofagalloninthetime(4hours)ittakeshertomakeapizza・SincePafsopportunitycostofmakingpizzaislessthanKris's,Pathasacomparativeadvantageinmakingpizza.b・SincePathasacomparativeadvantageinmakingpizza,shewillmakepizza\nandexchangeitforrootbeerthatKrismakes.C・Thehighestpriceofpizzaintermsofrootbeerthatwillmakebothroommatesbetteroffis2/3gallonsofrootbeer.Ifthepricewerehigherthanthat,thenKriswouldprefermakingherownpizza(atanopportunitycostof2/3gallonsofrootbeer)ratherthantradingforpizzathatPatmakes・Thelowestpriceofpizzaintermsofrootbeerthatwillmakebothroommatesbetteroffis1/2gallonofrootbeer.Ifthepricewerelowerthanthat,thenPatwouldprefermakingherownrootbeer(shecanmake1/2gallonofrootbeerinsteadofmakingapizza)ratherthantradingforrootbeerthatKrismakes・5.a.SinceaCanadianworkercanmakeeithertwocarsayearor30bushelsofwheat,theopportunitycostofacaris15bushelsofwheat.Similarly,theopportunitycostofabushelofwheatis1/15ofacar.Theopportunitycostsarethereciprocalsofeachother.b.SeeFigure3-4.Ifall10millionworkersproducetwocarseach,theyproduceatotalof20millioncars,whichistheverticalinterceptoftheproduct!onpossibilitiesfrontier.Ifall10millionworkersproduce30bushelsofwheateach,theyproduceatotalof300millionbushels,whichisthehorizontalinterceptoftheproductionpossibilitiesfrontier.Sincethetradeoffbetweencarsandwheatisalwaysthesame,theproductionpossibilitiesfrontierisastraightline.IfCanadachoosestoconsume10millioncars,itwillneed5millionworkersdevotedtocarproduction.Thatleaves5millionworkerstoproducewheat,whowillproduceatotalof150millionbushels(5millionworkerstimes30bushelsperworker).ThisisshownaspointAonFigure3-4.C・IftheUnitedStatesbuys10millioncarsfromCanadaandCanadacontinuestoconsume10millioncars,thenCanadawillneedtoproduceatotalof20millioncars・SoCanadawillbeproducingattheverticalinterceptoftheproductionpossibilitiesfrontier.ButifCanadagets20bushelsofwheatpercar,itwillbeabletoconsume200millionbushelsofwheat,alongwiththe10millioncars・ThisisshownaspointBinthefigure・Canadashouldacceptthedealbecauseitgetsthesamenumberofcarsand50millionmorebushesofwheat.\no2(suowlu)10BtI150200300Wheat(millionsofbushels)Figure3-46.Thoughtheprofessorcoulddobothwritinganddatacollectionfasterthanthestudent(thatis,hehasanabsoluteadvantageinboth),histimeislimited.Iftheprofessor'scomparativeadvantageisinwriting,itmakessenseforhimtopayastudenttocollectthedata,sincethatsthestudent'scomparativeadvantage・7.a.EnglishworkershaveanabsoluteadvantageoverScottishworkersinproducingscones,sinceEnglishworkersproducemoresconesperhour(50vs.40).ScottishworkershaveanabsoluteadvantageoverEnglishworkersinproducingsweaters,sinceScottishworkersproducemoresweatersperhour(2vs.1)・Comparativeadvantagerunsthesameway.Englishworkers,whohaveanopportunitycostof1/50sweatersperscone(1sweaterperhourdividedby50sconesperhour),haveacomparativeadvantageinsconeproductionoverScottishworkers,whohaveanopportunitycostof1/20sweaterperscone(2sweatersperhourdividedby40sconesperhour).Scottishworkers,whohaveanopportunitycostof20sconespersweater(40sconesperhourdividedby2sweatersperhour),haveacomparativeadvantageinsweaterproductionoverEnglishworkers,whohaveanopportunitycostof50sconespersweater(50sconesperhourdividedby1sweaterperhour).b・IfEnglandandScotlanddecidetotrade,ScotlandwillproducesweatersandtradethemforsconesproducedinEngland・Atradewithapricebetween20and50sconespersweaterwillbenefitbothcountries,astheyllbegettingthetradedgoodatalowerpricethantheiropportunitycostofproducingthegoodintheirowncountry.\nc.EvenifaScottishworkerproducedjustonesweaterperhour,thecountrieswouldstillgainfromtrade,becauseScotiandwouldstillhaveacomparativeadvantageinproducingsweaters・Itsopportunitycostforsweaterswouldbehigherthanbefore(40sconespersweater,insteadof20sconespersweaterbefore).ButtherearestillgainsfromtradesinceEnglandhasahigheropportunitycost(50sconespersweater).6.a.Technologicaladvancelowerstheopportunitycostofproducingmeatforthefarmer.Theopportunitycostofproducingapointofmeatwas2poundsofpotatoes;ifsnow1/5poundsofpotatoes.Thusthefarmer'sopportunitycostofproducingpotatoesisnow5poundsofmeat.Sincetherancher?sopportunitycostofproducingpotatoesis8poundsofmeat,thefarmerstillhasacomparativeadvantageinproducingpotatoesandtherancherstillhasacomparativeadvantageinproducingmeat.b・Nowthefarmerwon'tbewillingtotradeapoundofpotatoesfor3poundsofmeatbecauseifheproducedonelesspoundofpotatoes,hecouldproduce5morepoundsofmeat.Sothetradewouldbebadforthefarmer,ashewouldthenbeconsuminginsidehisproductionpossibilitiesfrontier.c.Thefarmerandrancherwouldnowbewillingtotradeonepoundofpotatoesforanamountbetween5and8poundsofmeat,withthepotatoesbeingproducedbythefarmerandthemeatbeingproducedbytherancher.9・a.Withnotrade,onepairofwhitesockstradesforonepairofredsocksinBoston,sinceproductivityisthesameforthetwotypesofsocks・ThepriceinChicagois2pairsofredsocksperpairofwhitesocks・b.Bostonhasanabsoluteadvantageintheproduct!onofbothtypesofsocks,sinceaworkerinBostonproducesmore(3pairsofsocksperhour)thanaworkerinChicago(2pairsofredsocksperhouror1pairofwhitesocksperhour).Chicagohasacomparativeadvantageinproducingredsocks,sincetheopportunitycostofproducingapairofredsocksinChicagois1/2pairofwhitesocks,whiletheopportunitycostofproducingapairofredsocksinBostonis1pairofwhitesocks・Bostonhasacomparativeadvantageinproducingwhitesocks,sincetheopportunitycostofproducingapairofwhitesocksinBostonis1pairofredsocks,whiletheopportunitycostofproducingapairofwhitesocksinChicagois2pairsofredsocks.c.Iftheytradesocks,Bostonwillproducewhitesocksforexport,sinceithasthecomparativeadvantageinwhitesocks,whileChicagoproducesredsocksforexport,whichisChicago'scomparativeadvantage.\nd.Tradecanoccuratanypricebetween1and2pairsofredsocksperpairofwhitesocks・Atapricelowerthan1pairofredsocksperpairofwhitesocks,Bostonwillchoosetoproduceitsownredsocks(atacostof1pairofredsocksperpairofwhitesocks)insteadofbuyingthemfromChicago.Atapricehigherthan2pairsofredsocksperpairofwhitesocks,Chicagowillchoosetoproduceitsownwhitesocks(atacostof2pairsofredsocksperpairofwhitesocks)insteadofbuyingthemfromBoston.10.a.ThecostofallgoodsislowerinGermanythaninFranceinthesensethatallgoodscanbeproducedwithfewerworkerhours・b.ThecostofanygoodforwhichFrancehasacomparativeadvantageislowerinFrancethaninGermany.ThoughGermanyproducesallgoodswithlesslabor,thatlaborismorevaluable.Sothecostofproduction,intermsofopportunitycost,willbelowerinFranceforsomegoods・c.TradebetweenGermanyandFraneewillbenefitbothcountries・Foreachgoodinwhichithasacomparativeadvantage,eachcountryshouldproducemoregoodsthanitconsumes,tradingtheresttotheothercountry・Totalconsumptionwillbehigherinbothcountriesasaresult.11・a.True;twocountriescanachievegainsfromtradeevenifoneofthecountrieshasanabsoluteadvantageintheproductionofallgoods・Allthafsnecessaryisthateachcountryhaveacomparativeadvantageinsomegood・b.False;itisnottruethatsomepeoplehaveacomparativeadvantageineverythingtheydo.Infact,noonecanhaveacomparativeadvantageineveryth!ng.Comparativeadvantagereflectstheopportunitycostofonegoodoractivityintermsofanother.Ifyouhaveacomparativeadvantageinonething,youmusthaveacomparativedisadvantageintheotherthing.c.False;itisnottruethatifatradeisgoodforoneperson，itcan'tbegoodfortheotherone.Tradescananddobenefitbothsides―speciallytradesbasedoncomparativeadvantage・Ifbothsidesdidn'tbenefit,tradeswouldneveroccur.