草埔地下配电室均采用()气体灭火系统。由体积百分比为52%的氮气(N2)、40%的氩气(Ar)、8%的二氧化碳(CO2)配制而成的混合气体。

A、IG541
B、IC541
C、IG451
D、IQ541
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A

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Thefanswereveryexcited______DavidBeckhamcametotheshow.

A、so
B、because
C、but
D、and

Thetouristtradeisbooming.Withallthiscomingandgoing,you'dexpectgreaterunderstandingodevelopbetweenthenationsoftheworld.Notabitofit!Superbsystemsofcommunicationbyair,seaandlandmakeitpossibleforustovisiteachother'scountriesatamoderatecost.Whatwasoncethe'grandtour',reservedforonlytheveryrich,isnowwithineverybody'sgrasp?

Thepackagetourandcharteredflightsarenottobesneeredat.Moderntravelersenjoyalevelofcomfortwhichthelordsandladiesongrandtoursintheolddayscouldn'thavedreamedof.Butwhat'sthesenseofthismassexchangeofpopulationsifthenationsoftheworldremainbasicallyignorantofeachother?

Manytouristorganizationsaredirectlyresponsibleforthisstateofaffairs.Theydeliberatelysetouttoprotecttheirclientsfromtoomuchcontactwiththelocalpopulation.Themoderntouristleadsacosseted,shelteredlife.Helivesatinternationalhotels,whereheeatshisinternationalfoodandsipshisinternationaldrinkwhilehegazesatthenativesfromadistance.Conductedtourstoplacesofinterestarecarefullycensored.Thetouristisallowedtoseeonlywhattheorganizerswanthimtoseeandnomore.Astrictschedulemakesitimpossibleforthetouristtowanderoffonhisown;andanyway,languageisalwaysabarrier,soheisonlytoohappytobeprotectedinthisway.Atitsveryworst,thisleadstoanewandhideouskindofcolonization.

Thesummerquartersoftheinhabitantsoftheciteuniversitaire:aretemporarilyreestablishedontheislandofCorfu.BlackpoolisrecreatedatTorremolinoswherethetravelergoesnottoeatpaella,butfishandchips.Thesadthingaboutthissituationisthatitleadstothepersistenceofnationalstereotypes.Wedon'tseethepeopleofothernationsastheyreallyare,butaswehavebeenbroughtuptobelievetheyare.Youcantestthisforyourself.Takefivenationalities,say,French,German,English,AmericanandItalian.Nowinyourmind,matchthemwiththesefiveadjectives:musical,amorous,cold,pedantic,native.Farfromprovidinguswithanyinsightintothenationalcharacteristicsofthepeoplesjustmentioned,theseadjectivesactuallyactasbarriers.Sowhenyousetoutonyourtravels,theonlycharacteristicsyounoticearethosewhichconfirmyourpreconceptions.Youcomeawaywiththehighlyunoriginalandinaccurateimpressionthat,say,'Anglo-Saxonsarehypocrites'ofthat'Latinpeoplesshoutalot'.Youonlyhavetomakeafewforeignfriendstounderstandhowabsurdandharmfulnationalstereotypesare.Buthowcanyoumakeforeignfriendswhenthetouristtradedoesitsbesttopreventyou?Carriedtoanextreme,stereotypescanbepositivelydangerous.Wildgeneralizationsstirupracialhatredandblindustothebasicfact〞howtriteitsounds!每Thatallpeoplearehuman.Weareallsimilartoeachotherandatthesametimeallunique.

1.Thebesttitleforthispassageis

[A]Tourismcontributesnothingtoincreasingunderstandingbetweennations.

[B]Tourismistiresome.

[C]Conductedtourisdull.

[D]Tourismreallydoessomethingtoone'scountry.

2.Whatistheauthor'sattitudetowardtourism?

[A]apprehensive.[B]negative.[C]critical.[D]appreciative.

3.WhichwordinthefollowingisthebesttosummarizeLatinpeopleshoutalot?

[A]silent.[B]noisy.[C]lively.[D]active.

4.Thepurposeoftheauthor'scriticismistopointout

[A]conductedtourisdisappointing.

[B]thewayoftouringshouldbechanged.

[C]whentraveling,younoticecharacteristicswhichconfirmpreconception.

[D]nationalstereotypesshouldbechanged.

5.Whatis'grandtour'now?

[A]moderatecost.

[B]localsight-seeingisinvestigatedbythetouristorganization.

[C]peopleenjoythefirst-ratecomforts.

[D]everybodycanenjoythe'grandtour'

The____ofAIDShasledtoanexpansioninresearchseekingacure.

A、innovation
B、selection
C、proliferation
D、conviction

AsGilbertWhite,Darwin,andothersobservedlongago,allspeciesappeartohavetheinnatecapacitytoincreasetheirnumbersfromgenerationtogeneration.Thetaskforecologistsistountangletheenvironmentaandbiologicalfactorsthatholdthisintrinsiccapacityforpopulationgrowthincheckoverthelongrun.Thegreatvarietyofdynamicbehaviorsexhibitedbydifferentpopulationmakesthistaskmoredifficult:sompopulationsremainroughlyconstantfromyeartoyear;othersexhibitregularcyclesofabundanceandscarcity;stillothersvarywildly,withoutbreaksandcrashesthatareinsomecasesplainlycorrelatedwiththeweather,andinothercasesnot.Toimposesomeorderonthiskaleidoscopeofpatterns,oneschoolofthoughtproposesdividingpopulationsintotwogroups.Theseecologistspositthattherelativelysteadypopulationshavedensity-dependentgrowthparameters;thatis,ratesofbirth,death,andmigrationwhichdependstronglyonpopulationdensity.Thehighlyvaryingpopulationshavedensity-independentgrowthparameters,withvitalratesbuffetedbyenvironmentalevents;theseratesfluctuateinawaythatiswhollyindependentofpopulationdensity.Thisdichotomyhasitsuses,butitcancauseproblemsiftakentooliterally.Foronething,nopopulationcanbedrivenentirelybydensity-independentfactorsallthetime.Nomatterhowseverelyorunpredictablybirth,death,andmigrationratesmaybefluctuatingaroundtheirlong-termaverages,iftherewerenodensity-dependenteffects,thepopulationwould,inthelongrun,eitherincreaseordecreasewithoutbound(barringamiraclebywhichgainsandlossescanceledexactly)。Putanotherway,itmaybethatonaverage99percentofalldeathsinapopulationarisefromdensity-independentcauses,andonlyonepercentfromfactorsvaryingwithdensity.Thefactorsmakinguptheonepercentmayseemunimportant,andtheircausemaybecorrespondinglyhardtodetermine.Yet,whetherrecognizedornot,theywillusuallydeterminethelong-termaveragepopulationdensity.Inordertounderstandthenatureoftheecologist’sinvestigation,wemaythinkofthedensity-dependenteffectsongrowthparametersasthesignalecologistsaretryingtoisolateandinterpret,onethattendstomakethepopulationincreasefromrelativelylowvaluesordecreasefromrelativelyhighones,whilethedensity-independenteffectsacttoproducenoiseinthepopulationdynamics.Forpopulationsthatremainrelativelyconstant,orthatoscillatearoundrepeatedcycles,thesignalcanbefairlyeasilycharacterizedanditseffectsdescribed,eventhoughthecausativebiologicalmechanismmayremainunknown.Forirregularlyfluctuatingpopulations,wearelikelytohavetoofewobservationstohaveanyhopeofextractingthesignalfromtheoverwhelmingnoise.Butitnowseemsclearthatallpopulationsareregulatedbyamixtureofdensity-dependentanddensity-independenteffectsinvaryingproportions.

1.Theauthorofthetextisprimarilyconcernedwith

[A]Discussingtwocategoriesoffactorsthatcontrolpopulationgrowthandassessingtheirrelativeimportance.

[B]Describinghowgrowthratesinnaturalpopulationsfluctuateovertimeandexplainingwhythesechangesoccur.

[C]Proposingahypothesisconcerningpopulationsizeandsuggestingwaystotestit.

[D]Posingafundamentalquestionaboutenvironmentalfactorsinpopulationgrowthandpresentingsomecurrentlyacceptedanswer.

2.Itcanbeinferredfromthetextthattheauthorconsidersthedichotomydiscussedtobe

[A]Applicableonlytoerraticallyfluctuatingpopulations.

[B]instrumental,butonlyifitslimitationsarerecognized.

[C]Dangerouslymisleadinginmostcircumstances.

[D]Acompleteandsufficientwaytoaccountforobservedphenomena.

3.tothetext,allofthefollowingbehaviorshavebeenexhibitedbydifferentpopulationsEXCEPT

[A]Roughlyconstantpopulationlevelsfromyeartoyear.

[B]Regularcyclesofincreasesanddecreasesinnumbers.

[C]Erraticincreasesinnumberscorrelatedwiththeweather.

[D]Uncheckedincreasesinnumbersovermanygenerations.

4.Thediscussionconcerningpopulationinthethirdparagraphservesprimarilyto

[A]Demonstratethedifficultiesecologistsfaceinstudyingdensity-dependentfactorslimitingpopulationgrowth.

[B]Advocatemorerigorousstudyofdensity-dependentfactorsinpopulationgrowth.

[C]Provethatthedeathratesofanypopulationareneverentirelydensity-independent.

[D]underlinetheimportanceofevensmalldensity-dependentfactorsinregulatinglong-termpopulationdensities.

5.Inthetext,theauthordoesallofthefollowingEXCEPT

[A]Citetheviewsofotherbiologists.

[B]Defineabasicproblemthatthetextaddresses.

[C]Presentconceptualcategoriesusedbyotherbiologists.

[D]Describetheresultsofaparticularstudy.

Frankalmostneverreceivedanyeducation,()?

A、wouldhe
B、didhe
C、didn'the
D、wouldn'the
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