范兆斌微经网上作业答案

Chapter1

问题115分

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Thekeyassumptionunderlyingthetheoryofthefirmisthat:A.firmsareassumedtomaximizesalesrevenue.B.managersareassumedtomaximizethenumberofemployeesintheirdepartment.C.firmsareassumedtomaximizeprofits.D.noneoftheabove

问题135分

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Thetrade-offsfacingconsumersinclude:A.howtoallocateincomeacrossgoodsandserves.B.howtoallocateincomebetweenconsumptionandsavings.C.bothAandBD.noneoftheabove

问题165分

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Thepriceofatacowas$0.29in1970and$0.99in1993.TheCPIwas38.8in1970and144.0in1993.The1993priceofatacoin1970dollarsis:A.$0.08.B.$0.27.C.$0.34.D.$3.67.

问题175分

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Whichofthefollowingmarketshasthemostrestrictivegeographicboundary?地理界线A.ThemarketforretailgasolineB.Themarketforhousing

C.ThemarketforgoldD.Themarketforbeef

问题185分

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Whyismarketdefinitionimportantforeconomicdecisionmaking?A.Afirmisinterestedinknowingitsactualandpotentialcompetitors.B.Afirmwilldefineitsmarketinordertomaximizerevenue.C.Governmentregulatorsareinterestedinknowingtheeffectofmergersandacquisitionsoncompetitionandpricesinaparticularmarket.D.bothAandCE.bothAndB

问题195分

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WhatdoesitmeanwhentheCPIishigherthisyearthanlast?A.Therateofinflationhasincreased.

B.Therehasbeeninflationsincelastyear.

C.Realpriceshaveincreased.

D.Realpriceshavedecreased.Chapter2

问题45分

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Coffeeandcream:A.arebothluxurygoods.

B.arecomplements.

C.arebothmoreinelasticindemandinthelongrunthanintheshortrun.D.haveapositivecrosspriceelasticityofdemand.

问题105分

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WhichofthefollowingwillNOTcauseashiftinthesupplyofgasoline?A.Anincreaseinthewagerateofrefineryworkers

B.Adecreaseinthepriceofgasoline

C.AnimprovementinoilrefiningD.technologyAdecreaseinthepriceofcrudeoil

问题135分

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WhichofthefollowingwillcausethedemandcurveforBeatlesʹcompactdiscstoshifttotheright?

A.Anincreaseinthepriceofthediscs

B.Adecreaseinconsumersʹincomes

C.AnincreaseinthepriceofPhilCollins'latestcompactdisc(asubstitute)D.alloftheabove

E.noneoftheabove

问题145分

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WhichofthefollowingwillNOTcausearightwardshiftinthedemandcurveforbeer?A.Achangeinthepriceofbeer

B.AhealthstudyindicatingpositivehealthbenefitsofmoderatebeerconsumptionC.AnincreaseinthepriceofFrenchwine(asubstitute)D.Adecreaseinthepriceofpotatochips(acomplement)E.noneoftheaboveChapter3

问题15分

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GaryFranklinisamoviecritic.HeinventedtheFranklinScalewithwhichheratesmoviesfrom1to10(10beingbest).Whenaskedabouthisscale,Mr.Franklinexplained"thatitisasubjectivemeasureofmoviequality.Amoviewitharankingof10isnotnecessarily10timesbetterthanamoviewitharankingof1,butitisbetter.Amoviewitharankingof5isbetterthanamoviewitharankingof1,butisnotasgoodamoviewitharankingof10.That'sallitreallytellsyou."BasedonMr.Franklin'sdescription,hisscaleis:A)ordinalbutnotcardinal.B)cardinalbutnotordinal.

C)anobjectivestandardtojudgemovies.D)neithercardinalnorordinal.

问题75分

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Ifamarketbasketischangedbyaddingmoreofatleastonegood,thenrationalconsumerswill:A)rankthemarketbasketmorehighlyafterthechange.B)morelikelypreferadifferentmarketbasket.C)rankthemarketbasketasbeingjustasdesirableasbefore.D)beunabletodecidewhetherthefirstmarketbasketispreferredtothesecondorviceversa.E)haveindifferencecurvesthatcross.

问题115分

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ZoeisanexecutiveatDellComputerCompanywhoisinchargeofdesigningthenextversionoflaptopcomputers.Shewillconsidersuchfeaturesasscreensize,weight,processorspeed,andCDandDVDdrives.Giventhefactthatitiscostlytoincludemorefeaturesinnewproducts,whymightZoebeinterestedindataonhowmuchconsumerspaidforarangeoflaptopswithdifferentattributes?A)inordertoestimatewillingnesstopayforeachfeature.B)inordertosetanoptimalpriceforthelaptops.C)inordertodeterminethebestfeaturestoinclude.D)inordertoestimatewillingnesstotradeoffonefeatureforanother.E)alloftheabove

问题125分

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Inwhatwayscaneconomistshelpautomanufacturersestimatethemarginalrateofsubstitutionbetweenfeaturessuchasvehicleinteriorsizeandacceleration?A)Examiningproductioncostdata

B)ConductingconsumersurveysaboutwillingnesstopayforautofeaturesC)Solvingthestandardconsumermodel

D)StatisticallyanalyzinghistoricaldataonpurchasesofdifferenttypesofautosE)BandDonly

问题145分

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Supposethatamarketbasketoftwogoodsischangedbyaddingmoreofoneofthegoodsandsubtractingoneunitoftheother.Theconsumerwill:A)rankthemarketbasketmorehighlyafterthechange.B)rankthemarketbasketmorehighlybeforethechange.C)rankthemarketbasketjustasdesirableasbefore.D)anyoneoftheabovestatementsmaybetrue.

问题165分

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Whichofthefollowingistrueabouttheindifferencecurvewhereonecommodity(suchaspollution)is"bad"?A)Ithasanegativeslope..B)Ithasapositiveslope.

C)Itishorizontal.D)Itisvertical

问题185分

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Envisionagraphwithmeatonthehorizontalaxisandvegetablesontheverticalaxis.Astrictvegetarianwouldhaveindifferencecurvesthatare:A)verticallines.

B)horizontallines.

C)diagonalstraightlines.

D)rightangles.

E)upwardsloping.

问题205分

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Janeistryingtodecidewhichcoursestotakenextsemester.Shehasnarroweddownherchoicetotwocourses,Econ1andEcon2.Nowsheishavingtroubleandcannotdecidewhichofthetwocoursestotake.It'snotthatsheisindifferentbetweenthetwocourses,shejustcannotdecide.Aneconomistwouldsaythatthisisanexampleofpreferencesthat:A)arenottransitive.

B)areincomplete.

C)violatetheassumptionthatmoreispreferredtoless.D)alloftheaboveChapter4

问题25分

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Thechangeinthepriceofonegoodhasnoeffectonthequantitydemandedofanothergood.Thesegoodsare:A)complements.

B)substitutes.

C)bothinferior.

D)bothGiffengoods.

E)noneoftheabove

问题45分

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Anindividualdemandcurvecanbederivedfromthe______curve.A)price-consumption

B)price-income

C)income-substitution

D)income-consumption

E)Engel

问题55分

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Whichofthefollowingclaimsistrueateachpointalongaprice-consumptioncurve?A)Utilityismaximizedbutincomeisnotallspent.

B)Allincomeisspent,bututilityisnotmaximized.

C)Utilityismaximized,andallincomeisspent.

D)Thelevelofutilityisconstant.

问题65分

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Whichofthefollowingistrueregardingincomealongaprice-consumptioncurve?A)Incomeisincreasing.

B)Incomeisdecreasing.

C)Incomeisconstant.

D)Thelevelofincomedependsonthelevelofutility.

问题75分

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Whichofthefollowingistrueregardingutilityalongaprice-consumptioncurve?A)Itisconstant.B)Itchangesfrompointtopoint.

C)Itchangesonlyifincomechanges.D)Itchangesonlyfornormalgoods.

问题85分

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Theincome-consumptioncurveA)illustratesthecombinationsofincomesneededwithvariouslevelsofconsumptionofagood.B)isanothernameforincome-demandcurve.

C)illustratestheutility-maximizingcombinationsofgoodsassociatedwitheveryincomelevel.D)showstheutility-maximizingquantityofsomegood(onthehorizontalaxis)asafunctionofincome(ontheverticalaxis).

问题105分

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Whichofthefollowinggoodshasalow,butpositive,incomeelasticityofdemand?A)furniture.

B)newcars.

C)healthinsurance.

D)alloftheabove

E)noneoftheabove

问题115分

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IfanEngelcurvehasapositiveslopeA)bothgoodsarenormal.

B)thegoodonthehorizontalaxisisnormal

C)asthepriceofthegoodonthehorizontalaxisincreases,moreofbothgoodsinconsumed.D)asthepriceofthegoodontheverticalaxisincreases,moreofthegoodonthehorizontalaxisisconsumed.

问题135分

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Whentheincome-consumptioncurvehasapositiveslopethroughoutitsentirelength,wecanconcludethatA)bothgoodsareinferior.

B)bothgoodsarenormal.

C)thegoodonthevertical(y)axisisinferior.

D)thegoodonthehorizontal(x)axisisinferior

问题145分

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ConsidertwogoodsXandYavailableforconsumption.AssumethatthepriceofXchangeswhilethepriceofYremainsfixed.Forthesetwogoods,theprice-consumptioncurveillustratestheA)relationshipbetweenthepriceofXandconsumptionofY.B)utility-maximizingcombinationsofXandYforeachpriceofX.C)relationshipbetweenthepriceofYandtheconsumptionofX.D)utility-maximizingcombinationsofXandYforeachquantityofX.

问题155分

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ConsideragraphonwhichonegoodYisontheverticalaxisandtheonlyothergoodXisonthehorizontalaxis.Onthisgraphtheincome-consumptioncurvehasapositiveslopeforlowincomes,thenittakesazeroslopeforahigherincome,andthenittakesanegativeslopeforevenhigherincomes(thecurvelookslikeanarc,firstrisingandthenfallingasincomeincreases).Thiscurveillustratesthat,forallincomelevels,A)bothXandYarenormal.B)onlyYisnormal.

C)bothXandYareinferior.D)onlyXisnormal.

问题165分

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AccordingtoasurveybytheU.S.BureauofLaborStatistics,whichofthefollowingstatementsaboutannualU.S.householdconsumerexpendituresisfalse?A)Theincomeelasticityofdemandforentertainmentispositive.B)Theincomeelasticityofdemandforowner-occupiedhousingispositive.C)Theincomeelasticityofdemandforrentalhousingispositive.D)Theincomeelasticityofdemandforhealthcareispositive.E)Averagefamilyexpendituresincreasewithincome.

问题185分

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Jon'sincome-consumptioncurveisastraightlinefromtheoriginwithapositiveslope.NowsupposethatJon'spreferenceschangesuchthathisincome-consumptioncurveremainsastraightlinebutrotates15degreesclockwise.Jon'sdemandcurveforthegoodonthe

horizontalaxisA)willshiftleft.B)willshiftright.

C)willnotchange.D)mightdoanyoftheabove.

问题195分

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Supposethataconsumerregardstwotypesofsoapasperfectsubstitutesforoneanother.ThepriceconsumptionpathgeneratedbychangingthepriceofonetypeofsoapA)isalwaysupwardsloping.

B)isalwayshorizontal.

C)isalwaysvertical.D)correspondswiththeaxisforthecheapersoap.E)correspondswiththeaxisforthemoreexpensivesoap.

问题205分

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Yourincomeresponseforbicycleridingchangeswiththeamountofincomeyouearn.Atlowlevelsofincome,youviewbicycleridingasaninferiorgoodandsubstituteothertypesoftransportation(e.g.,autotravel)asyourincomerises.However,youviewbicycleridingasanormalgoodafteryourincomerisesaboveaparticularlevel.WhatshapedoesyourEngelcurveforbicycleridinghave?A)Verticalline

B)Horizontalline

C)C-shaped

D)Upwardsloping

E)noneoftheaboveChapter6

问题15分

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AproductionfunctiondefinestheoutputthatcanbeproducedA)atthelowestcost,giventheinputsavailable.

B)fortheaveragefirm.

C)ifthefirmistechnicallyefficient.

D)inagiventimeperiodifnoadditionalinputsarehired.E)astechnologychangesovertime.

问题25分

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AproductionfunctionassumesagivenA)technology.

B)setofinputprices.

C)ratioofinputprices.

D)amountofcapitalandlabor.

E)amountofoutput.

问题105分

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ThelawofdiminishingreturnsreferstodiminishingA)totalreturns.B)marginalreturns.

C)averagereturns.D)allofthese.

问题135分

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Whentheaverageproductisdecreasing,marginalproductA)equalsaverageproduct.B)isincreasing.

C)exceedsaverageproduct.

D)isdecreasing.

E)islessthanaverageproduct.

问题155分

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WhichofthefollowingideaswerecentraltotheconclusionsdrawnbyThomasMalthusinhis1798"EssayonthePrincipleofPopulation"?A)Short-runtimeperiodB)Shortageoflabor

C)Lawofdiminishingresourceavailability

D)Lawofdiminishingreturns

问题165分

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ThelawofdiminishingreturnsassumesthatA)thereisatleastonefixedinput.

B)allinputsarechangedbythesamepercentage.C)additionalinputsareaddedinsmallerandsmallerincrements.D)allinputsareheldconstant.

问题175分

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AccordingtothelawofdiminishingreturnsA)thetotalproductofaninputwilleventuallybenegative.B)thetotalproductofaninputwilleventuallydecline.C)themarginalproductofaninputwilleventuallybenegative.D)themarginalproductofaninputwilleventuallydecline.E)noneoftheabove

问题185分

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Inacertaintextilefirm,laboristheonlyshorttermvariableinput.Themanagernoticesthatthemarginalproductoflaboristhesameforeachunitoflabor,whichimpliesthatA)theaverageproductoflaborisalwaysgreaterthatthemarginalproductoflaborB)theaverageproductoflaborisalwaysequaltothemarginalproductoflaborC)theaverageproductoflaborisalwayslessthanthemarginalproductoflaborD)asmorelaborisused,theaverageproductoflaborfallsE)thereisnounambiguousrelationshipbetweenlabor'smarginalandaverageproducts.

问题195分

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Atagivenleveloflaboremployment,knowingthedifferencebetweentheaverageproductoflaborandthemarginalproductoflabortellsyouA)whetherincreasinglaboruseraisesoutput.B)whetherincreasinglaborusechangesthemarginalproductoflabor.C)whethereconomiesofscaleexist.D)whetherthelawofdiminishingreturnsapplies.E)howincreasinglaborusealterstheaverageproductoflabor.

问题205分

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IfthelawofdiminishingreturnsappliestolaborthenA)themarginalproductoflabormusteventuallybecomenegative.B)theaverageproductoflabormusteventuallybecomenegative.C)themarginalproductoflabormustriseandthenfallasemploymentrises.D)theaverageproductoflabormustriseandthenfallasemploymentincreases.E)aftersomelevelofemployment,themarginalproductoflabormustfall.Chapter7

问题55分

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Constantinepurchased100sharesofIBMstockseveralyearsagofor$150pershare.Thepriceoftheseshareshasfallento$55pershare.Constantine'sinvestmentstrategyis"buylow,sell

high."Therefore,hewillnotsellhisIBMstockuntilthepricerisesabove$150pershare.Ifhesellsatapricelowerthan$150persharehewillhave"boughthighandsoldlow."

ConstantineA)iscorrectandshowsasolidcommandofthenatureofopportunitycost.B)isincorrectbecausetheoriginalpricepaidforthesharesisasunkcostandshouldhavenobearingonwhetherthesharesshouldbeheldorsold.C)isincorrectbecausewhenthepriceofastockfalls,thelawofdemandstatesthatheshouldbuymoreshares.D)isincorrectbecauseittreatsthepriceofthesharesasanexplicitcost.

问题65分

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InorderforataxicabtobeoperatedinNewYorkCity,itmusthaveamedalliononitshood.Medallionsareexpensive,butcanberesold,andarethereforeanexampleofA)afixedcost.

B)avariablecost.

C)animplicitcost.

D)anopportunitycost.

E)asunkcost.

问题75分

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ProspectivesunkcostsA)arerelevanttoeconomicdecision-making.

B)areconsideredasinvestmentdecisions.

C)riseasoutputrises.

D)donotoccurwhenoutputequalszero.

问题115分

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Whichofthefollowingcostsalwaysdeclinesasoutputincreases?A)Averagecost

B)Marginalcost

C)Fixedcost

D)Averagefixedcost

E)Averagevariablecost

问题205分

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Foranygivenlevelofoutput:A)marginalcostmustbegreaterthanaveragecost.B)averagevariablecostmustbegreaterthanaveragefixedcost.C)averagefixedcostmustbegreaterthanaveragevariablecost.D)fixedcostmustbegreaterthanvariablecost.

E)Noneoftheaboveisnecessarilycorrect.Chapter8

问题2得5分，满分5分

Ifmanagersdonotchoosetomaximizeprofit,butpursuesomeothergoalsuchasrevenuemaximizationorgrowth,正确答案：

A)theyaremorelikelytobecometakeovertargetsofprofit-maximizingfirms.

问题7得5分，满分5分

Inmanyruralareas,electricgenerationanddistributionutilitieswereinitiallysetupascooperativesinwhichtheelectricitycustomersweremember-owners.Likemostcooperatives,theobjectiveofthesefirmswasto:正确答案：

C)operateatzeroprofitinordertoprovidelowelectricitypricesforthemember-owners.

问题8得5分，满分5分

Anassociationofbusinessesthatarejointlyownedandoperatedbymembersformutualbenefitisa:正确答案：

C)cooperative.

Chapter10

问题10得5分，满分5分

Whenaperunittaxisimposedonthesaleofaproductofamonopolist,theresultingpriceincreasewill正确答案：

D)notalwaysbelessthanthetax.

问题16得5分，满分5分

Amonopolisthasdeterminedthatatthecurrentlevelofoutputthepriceelasticityofdemandis-0.15.Whichofthefollowingstatementsistrue?正确答案：

A)Thefirmshouldcutoutput.

问题17得5分，满分5分

Amonopolisthassetherlevelofoutputtomaximizeprofit.Thefirm'smarginalrevenueis$20,andthepriceelasticityofdemandis-2.0.Thefirm'sprofitmaximizingpriceisapproximately:正确答案：

C)$40Chapter14

问题3得5分，满分5分

Otherthingsbeingequal,themarginalrevenueproduct(MRP)curveforacompetitiveseller正确答案：

C)liesabovetheMRPcurveforamonopolist.

问题4得5分，满分5分

Whatcanaccountforthenegativeslopeofthemarginalrevenueproductcurve?正确答案：

B)Diminishingmarginalreturns

问题5得5分，满分5分

Ifthemarketforlaborisperfectlycompetitive,theprofitmaximizingleveloflaboroccurswhere正确答案：

D)MRPL=W.

问题6得5分，满分5分

Ifleisureisanormalgood,thentheincomeeffectofadecreaseinwagewill正确答案：

B)increasethenumberofhoursworked.

问题7得5分，满分5分

Thesubstitutioneffectofadecreaseinthewagewill正确答案：

B)increaseleisure,regardlessofwhetherleisureisanormalorinferiorgood.

问题9得5分，满分5分

Anincreaseintechnologythatenhanceslaborproductivitywilllikelyresultin:正确答案：

B)anincreaseinlaboremploymentandanincreaseinthewagerate.

问题10得5分，满分5分

Whenthefactormarketispurelycompetitive,thefirmʹsaverageexpenditurecurveforafactorofproductionis正确答案：

C)identicaltothemarginalexpenditurecurve.

问题11得5分，满分5分

Underwhatcircumstancesarethemarginalexpenditureforaninputandtheaverageexpenditurealwaysequal?Wherethereisa正确答案：

A)competitivebuyer.

问题12得5分，满分5分

Afirmpurchasesafactorofproductioninacompetitivemarket.AtthecurrentpurchaseratetheMRPofthefactorisgreaterthanthemarginalexpenditureforthefactor.Thus,thefirm正确答案：

D)canincreaseprofitbyexpandingtheemploymentofthefactorofproduction.

问题13得5分，满分5分

Assumethatasthewageraterisesaworker'ssubstitutioneffectforleisureislargerthantheincomeeffect.Wecanconcludethatinthisregion,theworker's正确答案：

B)laborsupplycurvewillhavetheusualupwardslope.

问题14得5分，满分5分

Theindustrydemandcurveforlaboristhe正确答案：

A)horizontalsumofindividualfirmlabordemandcurves.

问题17得5分，满分5分

TheAcmeCompanyisaperfectcompetitorinitsinputmarketsanditsoutputmarket.Itsaverageproductoflaboris30,themarginalproductoflaboris20,thepriceoflaboris$20,andthepriceoftheoutputis$5.ForAcmeCompany,themarginalrevenueproductoflabor正确答案：

A)is$100.

问题18得5分，满分5分

TheAcmeCompanyisaperfectcompetitorinitsinputmarketsandamonopolistinitsoutputmarket.Itsaverageproductoflaboris30,themarginalproductoflaboris20,thepriceoflaboris$20,andthepriceoftheoutputis$5.ForAcmeCompany,themarginalrevenue

productoflabor正确答案：

E)cannotbedeterminedwiththeinformationprovided.

问题19得5分，满分5分

TheAcmeCompanyisaperfectcompetitorinitsinputmarketsandamonopolistinitsoutputmarket.Themarginalproductoflaboris20andthepriceofAcme'soutputis$10.ForAcmeCompany,themarginalrevenueproductoflaboris正确答案：

D)lessthan$200.

问题20得5分，满分5分

TheAcmeCompanyisaperfectcompetitorinitsinputmarketsanditsoutputmarket.Itsaverageproductoflaborisatitsmaximumandequals30.Themarginalrevenueproductoflaboris$300.Thepriceofitsoutput正确答案：

B)is$10.Chapter16Chapter17

问题135分

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Whenfirmsparticipateingrouphealthinsuranceforallemployees,itA)raisesratesforeveryone,becauseitbringsunhealthypeopleintothepool.B)raisesratesforunhealthypeople.

C)maylowerratesforallpeopletotheextentthatitkeepshealthypeopleinthepool.D)preventsunhealthypeoplefrom"selectingout,"tothedetrimentofhealthypeople.E)increasestheamountofinformationavailabletoinsurersaboutthepopulation.

问题165分

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Inthearenaofasymmetricinformation,standardization(forexample,menusatMcDonald'srestaurants)isasubstituteforA)quality.

B)governmentregulation.

C)reputationofindividualsellers.

D)firms'distinguishingamongbuyers.

E)firms'segregationofbuyers.

问题195分

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HowdoonlineauctionsiteslikeEbayattempttoovercometheasymmetricinformationproblemsassociatedwithgoodsthatthebuyercannotpersonallyinspectbeforepurchaseA)Theonlineauctionfirmonlyallowshigh-qualitymerchandisetobesoldattheirsite.B)Thepreviousperformance(reputations)ofthebuyerandsellerarepostedforpublicreview.C)Buyerscantakereceiptofanygoodsbeforetheyhavetopaytheseller.D)alloftheaboveChapter18

问题25分

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Constructingplasticcontainersproducesairpollutants.Therefore,inthemarketforplasticcontainers,A)themarginalsocialcostcurveisaboveandtotherightofthedemandcurve.B)themarginalsocialcostcurveisbelowandtotheleftofthedemandcurve.C)themarginalsocialcostcurveisaboveandtotheleftofthesupplycurve.D)themarginalsocialcostcurveisbelowandtotherightofthesupplycurve.E)thereisagapbetweenquantitysuppliedandquantitydemandedinequilibrium.

问题35分

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Drycleaningofclothingproducesairpollutants.Therefore,inthemarketfordrycleaningservices,theequilibriumpriceA)andoutputaretoolowtobeoptimal.

B)andoutputaretoohightobeoptimal.

C)istoolowtobeoptimal,andequilibriumquantityistoohigh.D)istoohightobeoptimal,andequilibriumquantityistoolow.E)isoptimal,butthereisanexcesssupply.

问题55分

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Becausetruckingasanindustryinvolvesthegenerationofpollutantsinengineexhaust,A)thesupplycurveoftruckingservicesoverstatesthetruecostofprovidingthoseservices.B)thesupplycurveoftruckingservicesunderstatesthetruecostofprovidingthose

services.C)thedemandcurvefortruckingservicesoverstatesthetruebenefitofprovidingthose

services.D)thedemandcurvefortruckingservicesunderstatesthetruebenefitofprovidingthose

services.E)themarketfortruckingserviceswillalwaysbeawayfromequilibriumbyanamount

equaltothevalueoftheexternality.

问题65分

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Becauseaircargoasanindustryinvolvesthegenerationofpollutantsinengineexhaust,the

equilibriumpriceofaircargoservicesA)isabovetheoptimallevel,andquantityisbelowtheoptimallevel.B)isbelowtheoptimallevel,andquantityisabovetheoptimallevel.C)andquantityoftruckingservicesarebothabovetheoptimallevel.D)andquantityoftruckingservicesarebothbelowtheoptimallevel.E)mus