压力的常用国际单位表达中不正确的是()。

A、N/m2
B、kPa
C、MPa
D、bar
查看答案
正确答案:

D

答案解析:

压力的定义是垂直作用于流体或固体界面单位面积上的力,即N/m2,压力的基本国际单位是Pa,1kPa=103Pa,1MPa=106Pa。D项,bar是工程中经常用到的压力单位,但不是国际单位。

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PartIVTranslation

Yetcowboyslikedtheirwayoflife.Theylivedinawildandopencountry.Theylivedalifeofadventureandfreedom.(PassageThree)

Passage2

Questions6to10arebasedonthefollowingpassage:

Whenaluminumwasfirstproducedaboutahundredandfiftyyearsago,itwassodifficulttoseparateformtheoresinwhichitwasfoundthatitspricewashigherthanthatofgold.Thepriceremainedhighuntilanewprocesswasdiscoveredforrefiningthemetalwiththeaidofelectricityapproximatelythreequartersofacenturylater.Thenewmethodwassomuchcheaperthataluminumbecausepracticalformanypurposes,oneofwhichwasmakingpotsandpans.

Aluminumislightweight,rustproofandeasilyshapedintodifferentforms.Bymixingitwithothermetals,scientistshavebeenabletoproduceavarietyofalloys,someofwhichhavethestrengthofsteelbutweighonlyonethirdasmuch.

Today,theusesofaluminumareinnumerable.Perhapsitsmostimportantuseisintransportation.Aluminumisfoundintheengineofautomobiles,inthehullsofboats.Itisalsousedinmanypartsofairplanes.Infact,thehuge“airbus”planeswouldprobablyneverhavebeenproducedifaluminumdidnotexist.Bymakingvehicleslighterinweightaluminumhasgreatlyreducedtheamountoffuelneededtomovethem,Aluminumisalsobeingusedextensivelyinthebuildingindustryinsomecountries.

Sincealuminumissuchaversatile(多用的)metal,itisfortunatethatbauxite(铝土矿),whichisoneofitschiefsources,isalsooneoftheearth’smostplentifulsubstances.Asthesourceofaluminumisalmostinexhaustible,wecanexpectthatmoreandmoreuseswillbefoundforthisversatilemetal.

6.Thepriceofaluminumwassharplyreducedwhenpeoplediscoveredanewrefiningprocesswiththeaidof.

A.windB.solarenergyC.hydraulicpowerD.electricity

7.Aluminumis.

A.lightweight,rustproofbutnoteasilyshapedintodifferentforms

B.heavyweight,rustproofandeasilyshapedintodifferentforms

C.lightweight,rustproofandeasilyshapedintodifferentforms

D.lightweightandeasilyshapedintodifferentformsbutitiseasytobecomerusty

8.WhichofthefollowingisNOTtrue?

A.Aluminumiswidelyusedintransportation.

B.Aluminumisalsousedinmanypartsofairplanes.

C.Aluminumisbeingusedextensivelyinthebuildingindustry.

D.Aluminumisnotusedinitspureform.

9.Aluminumisfoundonearthmostlyintheformof.

A.puremetalB.bauxiteC.goldD.liquid

10.Whatisthepassagetalkingabout?

A.Thefeaturesofaluminumanditsfunctions.B.Theprocessofaluminum.

C.Thediscoveryofaluminum.D.Thepromisingfutureofaluminum.

PartIIVocabularyandStructure

Directions:Inthisparttherearefortyincompletesentences.Eachsentenceisfollowedbyfourchoices.ChoosetheonethatbestcompletesthesentenceandthenmarkyouranswerontheAnswerSheet.

21.Theteacherthestudentsonatourthroughtheartmuseum.

A.madeB.indicatedC.forcedD.took

22.Tom’sparentsdiedwhenhewasachild,sohewasbyhisrelatives.

A.grownupB.broughtupC.raisedD.fedup

23.Hereismycard.Let’skeepin.

A.touchB.relationC.connectionD.friendship

24.Sofarthereisnoproofpeoplefromotherplanetsdoexist.

A.whichB.howC.whatD.that

25.Thenewspapersreportedyesterdayseveralontheboundariesofthesetwocountries.

A.incidentsB.happeningsC.eventsD.accidents

26.We’veworkedouttheplanandnowwemustputitinto.

A.factB.realityC.practiceD.deed

27.Hedidn’tandsohefailedtheexamination.

A.workenoughhardB.hardworkenoughC.hardenoughworkD.workhardenough

28.NotuntilMr.SmithcametoChinawhatkindofcountrysheis.

A.heknewB.hedidn’tknowC.didheknowD.hecouldn’tknow

29.Scientistssayitmaybetenyearsthismedicinewasputtouse.

A.sinceB.beforeC.afterD.when

30.Insomecountries,iscalled“equality”doesnotreallymeanequalrightsforallpeople.

A.thatB.whatC.whichD.how

31.Wedidn’tknowhistelephonenumber,otherwisewehim.

A.wouldtelephoneB.wouldhavetelephone

C.hadtelephonedD.musthavetelephoned

32.We’vemissedthelastbus,I’mafraidwehavenobuttotakeataxi.

A.wayB.possibilityC.choiceD.selection

33.Luckily,mostsheepthefloodlastmonth.

A.enduredB.survivedC.livedD.passed

34.Myparentsalwaysletmehavemyownofliving.

A.wayB.methodC.mannerD.fashion

35.Likeotherlanguageskills,readingrequirespractice.

A.themostofB.muchoftheC.mostoftheD.moreofthe

36.Itisonlythroughpracticeonewillbeabletoswimskillfully.

A.whatB.whoC.thatD.which

37.Thebrainiscapableofignoringpainmessageoftoconcentrateonotheractivities.

A.itallowedB.isitallowedC.allowedD.allowedit

38.Don’tworry,Ihavealreadythemthedecision.

A.informed;withB.informed;ofC.informed;forD.informed;that

39.Thechildwassorryhismotherwhenhearrivedatthestation.

A.tomissB.havingmissedC.missingD.tohavemissed

40.Iwonderwhyhetodiscusstheproblematthemeeting.

A.declinedB.rejectedC.refusedD.delayed

41.Youcanhangupwhatyoulikeonthesewalls.

A.bareB.emptyC.blankD.vacant

42.Accordingtoa,themajoritywouldratherhavenewspaperswithoutagovernmentthanagovernmentwithoutnewspapers.

A.electionB.campaignC.pollD.vote

43.Thepopulationofthevillagehasdecreased150to500.

A.inB.atC.byD.with

44.ItseemsthatthereisthatIcan’tdo.

A.nothingB.anythingC.everythingD.none

45.Theyareoftencaringmoreaboutanimalsthanhumanbeings.

A.accusedifB.accusedwithC.chargedofD.chargedfor

46.agoodbeginningismade,thewordishalfdone.

A.AssoonasB.WhileC.AsD.Once

47.Georgecouldnothisfoolishmistake.

A.accountinB.countonC.countforD.accountfor

48.Wecameintothisfieldlate,sowemustworkhardtothelosttime.

A.makeupforB.makeoutC.keepupwithD.putupwith

49.Thenewlawwillcameintoonthedayitispassed.

A.effectB.useC.serviceD.existence

50.Wecanseparatethemixtureintothepurechemicalcompoundsitiscomposed.

A.inwhichB.ofwhatC.ofwhichD.fromwhich

51.Mrs.Lincolnhasthatsheisunabletogetajob.

A.suchsmalleducationB.solittleeducation

C.asuchlittleeducationD.asosmalleducation

52.Shecan’tpreventherlittleboyshootingbirds.

A.from;toB.on;atC.with;upD.from;at

53.Manycountriesareincreasingtheiruseofnaturalgas,windandotherformsof.

A.energyB.sourceC.powerD.material

54.Adarkenedskyinthedaytimeisusuallyandindicationthatastormis.

A.possiblecomingB.abouttotakeplace

C.closebyD.expectedtobesevere

55.Weallknowthatspeaklouderthanwords.

A.movementsB.performanceC.operationsD.actions

56.,hecouldnotcoverthewholedistanceinfifteenminutes.

A.FastashecanB.Ashecanranfast

C.IfhecanranfastD.Sinceheranfast

57.Agriculturalproductioninthatcountryhasincreasedinrecentyears.

A.vastlyB.strikinglyC.considerablyD.extremely

58.Peterhasplannedtosomemoneyeverymonthsothathecanbuyausedcarnextyear.

A.setasideB.setupC.setinD.setalong

59.AlthoughIspoketohimmanytimes,henevertookanyofwhatIsaid.

A.attentionB.noticeC.warningD.observation

60.Theyovercameallthedifficultiesandfulfilledtheplanthreemonthsaheadoftime,issomethingwehadnotexpected.

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