11级本期末考试

《11级本期末考试》由会员上传分享，免费在线阅读，更多相关内容在工程资料-天天文库。

1、11本科阅读理解Passage1Ifthepopulationoftheearthgoesonincreasingatitspresentrate,therewilleventuallynotbeenoughresourceslefttosustainlifeontheplanet.Bythemiddleofthe21stcentury,ifpresenttrendscontinue,wewillhaveusedupalltheoilthatdrivesourcars,forexample.Evenif

2、scientistsdevelopnewwaysoffeedingthehumanrace,thecrowdedconditionsonearthwillmakeitnecessaryforustolookforopenspacesomewhereelse.Butnoneoftheotherplanetsinoursolarsystemarecapableofsupportinglifeatpresent.Onepossiblesolutiontotheproblem,however,hasrecent

3、lybeensuggestedbyAmericanscientist,ProfessorCarlSagan.Saganbelievesthatbeforetheearth"sresourcesarecompletelyexhausteditwillbepossibletochangetheatmosphereofVenusandsocreateanewworldalmostaslargeasearthitself-ThedifficultisthatVenusismuchhotterthantheear

4、thandthereisonlyatinyamountofwaterthere.Saganproposesthatalgae（藻类）organismsthatcanliveinextremelyhotorcoldatmospheresandatthesametimeproduceoxygen,shouldbebredinconditionsimilartothoseonVenus.Assoonasthishasbeendone,thealgaewi11beplacedinsmal1rockets.Spa

5、ceshipwi11thenflytoVenusandfiretherocketsintotheatmosphere.Inafairlyshorttime,thealgaewillbreakdownthecarbondioxideintooxygenandcarbon.Whenthealgaehavedonetheirwork,theatmospherewillbecomecooler,butbeforememcansetfootonVenusitwi11benecessaryfortheoxygent

6、oproducerain.ThesurfaceoftheplanetwillstillbetoohotformantolandonitbuttherainwilleventuallyfallandinafewyearssomethinglikeearthwillbereproducedonVenus.1.Tnthelongrun,themostinsolubleproblemcausedbypopulationgrowthonearthwillprobablybethelackof.a.foodb.o订

7、c.spaced.resources2.CarlSaganbelievesthatVenusmightbecolonizedfromearthbecausea.itmightbepossibletochangeitsatmosphereb.itsatmosphereisthesameastheearth'sa.thereisagoodsupplyofwateronVenusb.thedaysonVenusarelongenough1.OnVenusthereisalotof.a.waterb.carbo

8、ndioxidec.carbonmonoxided.oxygen2.Algaeareplantsthatcan.a.liveinveryhottemperaturesb.liveinverycoldtemperaturesc.manufacturcoxygend.alloftheabove3.MancanlandonVenusonlywhen•a.thealgaehavedonetheirworkb.theatmosphcrcbecomes