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A
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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.