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下列关于数据库管理系统的叙述中,哪一条是错误的?

A、数据库管理系统是用户与操作系统之间的一个接口
B、数据库管理系统便于用户对数据库进行管理和维护
C、数据库管理系统能保证数据库中数据的安全性、完整性
D、仅提供编程语言,使得新的查询和处理代价高、费事
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正确答案:

A

答案解析:

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Passage1

Questions1to5arebasedonthefollowingpassage:

DoyouwanttosaywhatyouthinkinalettertothePresidentoftheUnitedStates?You’llgetareplyfromhim—writteninink,nottyped—afteronlyafewdays.

ThePresidentgetsabout4,000letterseveryweek.HeanswerseveryonewhowritestohimonspecialWhitesHousepaper.Buthedoesn’tneedalotoftimeforit.Infact,heonlygives20minutesaweektolookathispersonalcorrespondence.Hehasthemostmodernsecretaryintheworldtohelphim.

It’scomputer,worth£800,000,whichhasitsownroomsonthefirstflooroftheWhiteHouse.IthasabankofelectronicpenswhichwritelikethePresidentwrites,inhisfavoritelightblueink.EachletterthePresidentreceivesgetsanumber,accordingtothetypeofansweritneeds.Thepensthenwritethecorrectreplyforit,accordingtothenumber.Eachlettertakeslessthanasecondtowrite.AWhiteHouseofficialsaid,“It’snotimportantthatletterscomefromacomputer.EachlettersayswhatthePresidentwantstosay.”

1.forareplyfromthePresident.

A.YouhavetowaitalongtimeB.Youonlyhavetowaitseveraldays

C.YouhavetowaitatleastonemonthD.Youonlyhavetowaitafewweeks

2.ThereplyfromthePresident.

A.isalwaysprintedB.isalwaystyped

C.isalwayswrittenininkD.isalwayswrittenbyhimself

3.Ittakesthecomputertowritetenletters.

A.nomorethantensecondsB.alittlemorethantenseconds

C.lessthantensecondsD.atleastonesecond

4.Thecomputercanbedescribedas.

A.expensivebutefficientB.possessingabeautifulhandwriting

C.heavyandinefficientD.thePresident’smostreliablesecretary

5.Itcanbeinferredfromthepassagethat.

A.thePresidentneverreadsanyletterswrittentohimbyordinarypeople

B.thePresidenthiresaveryefficientsecretarytodealwithhiscorrespondence

C.thePresidentdoesnotreallycareaboutthelettershereceiveseveryweek

D.thePresidentisassuredthatthecomputerexpresshisviewsintheletters

Theywillneverreconcilethemselvesto____.

Passage2

Questions6to10arebasedonthefollowingpassage:

Thefoodweeatseemstohaveprofoundeffectsonourhealth.Althoughsciencehasmadeenormousstepsinmakingfoodmorefittoeat,ithas,atthesametime,mademanyfoodsunfittoeat.Someresearchhasshowntat40percentofcancerisrelatedtothedietaswell,especiallycancerofthecolon.Differentculturesatemorepronetogetcertainillnessesbecauseofthefoodthatischaracteristicinthesecultures.Thatfoodisrelatedtoillnessisnotanewdiscovery.In1945,governmentresearchersrealizedthatnitratesandnitrites,commonlyusedtopreservecolorinmeats,andotherfoodadditives,causedcancer.Yetthesecarcinogenicadditivesremaininourfood,anditbecomesmoredifficultallthetimetoknowwhichthingsonthepackaginglabelsofprocessedfoodarehelpfulorharmful.Theadditivesthatweeatarenotallsodirect.Farmersoftengivepenicillintobeefandpoultry,andbecauseofthis,penicillinhasbeenfoundinthemilkoftreatedcows.Sometimessimilardrugsareadministeredtoanimalsnotformedicinalpurposes,butforfinancialreasons.Thefarmersaresimplytryingtofattentheanimalsinordertoobtainahigherpriceonthemarket.AlthoughtheFoodandDrugAdministration(FDA)hastriedrepeatedlytocontroltheseprocedures,thepracticescontinue.

6.Howhassciencedoneadisservicetomankind?

A.Becauseofscience,mostofthefoodsweeattodayarecontaminated.

B.Ithascausedalackofinformationconcerningthevalueoffood.

C.Asaresultofscientificintervention,somepotentiallyharmfulsubstanceshasbeenaddedtoourfood.

D.Thescientistshavepreservedthecolorofmeats,butnotofvegetables.

7.Whatarenitratesusedfor?

A.Theypreservesflavorinpackagedfoods.

B.Theypreservethecolorofmeats.

C.Theyaretheobjectsofresearch.

D.Theycausetheanimalstobecomefatter.

8.TheFDAhastriedrepeatedlytocontrol.

A.theattempttofattentheanimals

B.theattempttocuresickanimals

C.theusingofdrugstoanimals

D.theusingofadditivestopreservethedoloroffood

9.Theword“carcinogenic”meansmostnearlythesameas.

A.trouble-makingB.color-retaining

C.money-savingD.cancer-causing

10.WhichofthefollowingstatementsisNOTtrue?

A.Drugsarealwaysgiventoanimalsformedicalreasons.

B.Someoftheadditivesinourfoodareaddedtothefooditselfandsomearegiventothelivinganimals.

C.Researchershaveknownaboutthepotentialhazardsofthefoodadditivesforoverthirty-fiveyears.

D.Foodmaycausefortypercentofcancerintheworld.

Scatteredthroughtheseasoftheworldarebillionsoftonsofsmallplantsandanimalscalledplankton.Mostoftheseplantsandanimalsaretoosmallforthehumaneyetosee.Theydriftaboutlazilywiththecurrents,providingabasicfoodformanylargeranimals.Planktonhasbeendescribedastheequivalentofthegrassesthatgrowonthedrylandcontinents,andthecomparisonisanappropriateone.Inpotentialfoodvaluehowever,planktonfaroutweighsthatofthelandgrasses.Onescientisthasestimatedthatwhilegrassesoftheworldproduceabout49billiontonsofvaluablecarbohydrateseachyear.Thesea’splanktongeneratesmorethantwiceasmuch.

Despiteitsenormousfoodpotential,littleeffortwasmadeuntilrecentlytofarmplanktonaswefarmgrassesonland.Nowmarinescientistshaveatlastbeguntostudythispossibility,especiallyasthesea’sresourcesloomevenmoreimportantasameansoffeedinganexpandingworldpopulation.

Nooneyethasseriouslysuggestedthat“planktonburgers”maysoonbecomepopulararoundtheworld.Asapossiblefarmedsupplementaryfoodsource,however,planktonisgainingconsiderableinterestamongmarinescientists.

Onetypeofplanktonthatseemstohavegreatharvestpossibilitiesisatinyshrimplikecreaturecalledkrill.Growingtotwoorthreeincheslong,krillprovidethemajorfoodforthegiantbluewhale,thelargestanimalevertoinhabittheEarth.Realizingthatthiswhalemaygrow100feetandweigh150tonsatmaturity,itisnotsurprisingthateachonedevoursmorethanonetonofkrilldaily.

Krillswimaboutjustbelowthesurfaceinhugeschoolssometimesmileswide,mainlyinthecoldAntarctic.Becauseoftheirpinkcolor,theyoftenappearasasolidreddishmasswhenviewedfromashiporfromtheair.Krillareveryhighinfoodvalue.Apoundofthesecrustaceanscontainsabout460calories—aboutthesameasshrimporlobster,towhichtheyarerelated.

Ifthekrillcanfeedsuchhugecreaturesaswhales,manyscientistsreason,theymustcertainlybecontendersasnewfoodsourceforhumans.

1.Whichofthefollowingbestportraystheorganizationofthepassage?

A.Theauthorpresentstheadvantagesanddisadvantagesofplanktonasafoodsource.

B.Theauthorquotespublicopiniontosupporttheargumentforfarmingplankton.

C.Theauthorclassifiesthedifferentfoodsourcesaccordingtoamountofcarbohydrate.

D.Theauthormakesageneralstatementaboutplanktonasafoodsourceandthenmovestoaspecificexample.

2.Accordingtothepassage,whyisplanktonregardedtobemorevaluablethanlandgrasses?

A.Itiseasiertocultivate.

B.Itproducesmorecarbohydrates.

C.Itdoesnotrequiresoil.

D.Itismorepalatable.

3.Whydoestheauthormention“planktonburgers”?

A.Todescribetheappearanceofonetypeofplankton.

B.Toillustratehowmuchplanktonawhaleconsumes.

C.Tosuggestplanktonasapossiblefoodsources.

D.Tocomparethefoodvaluesofbeefandplankton.

4.Whatismentionedasoneconspicuousfeatureofkrill?

A.Theyarethesmallestmarineanimals.

B.Theyarepinkincolor.

C.Theyaresimilarinsizetolobsters.

D.Theyhavegrasslikebodies.

5.Theauthormentionsallofthefollowingasreasonswhyplanktoncouldbeconsideredahumanfoodsourceexceptthatitis___.

A.highinfoodvalue.

B.inabundantsupplyintheoceans.

C.anappropriatefoodforotheranimals.

D.freeofchemicalsandpollutants.

GriffithworkedforafirmthatspecializedineconomicdevelopmentinWashingtonD.C.becausesheneededmoneytopayforherdebt.

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