在计算机网络中,表征数据传输有效性的指标是 ____。

A、误码率
B、频带利用率
C、信道容量
D、传输速率
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正确答案:

D

答案解析:

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翻译:

Cultureshockiscausedbytheanxietythatresultsfromlosingallfamiliarsignsandsymbolsofsocialintercourse.(PassageFour)

Passage3

Questions11to15arebasedonthefollowingpassage:

About70millionAmericansaretryingtolossweight.Thatisalmost1outofevery3peopleintheUnitedStates.Somepeoplegoonideas.Thismeanstheyeatlesscertainfoods,especiallyfatsandsugars.Otherpeopleexercisewithespecialequipment,takedietpills,orevenhavesurgery.Losingweightishardwork,anditcanalsocostalotofmoney.SowhydosomanypeopleintheUnitedStateswanttoloseweight?

ManypeopleintheUnitedStatesworryaboutnotlookingyoungandattractive.Formanypeople,lookinggoodalsomeansbeingthin.Otherpeopleworryabouttheirhealth.Manydoctorssaybeingoverweightisnothealthy.ButareAmericansreallyfat?Almost30millionAmericansweightatleast20percentmorethantheiridealweight.Infact,theUnitedStateisthemostoverweightcountryinthewild.“ThestoredfatofadultAmericansweight2.3trillionpounds,”saysUniversityofMassachusettsanthropologist(人类学家)GeorgeArmelagos.Hesaysburningoffthatstoredenergywouldproduceenoughpowerfor900,000carstogo12,000miles.

Losingweightishardwork,butmostpeoplewanttofindafastandeasywaytotakeofffat.Bookstoresselllotsofdietbooks.Thesebookstellreadershowtoloseweight.Eachyear,dozensofnewbookslikethesearewritten.Eachoneboaststohelppeopletogetridoffat.

11.WhichofthefollowingisNOTmentionedasawayoflosingweight?

A.Toeatlessfatsandsugars.B.Toworkhard.

12.ManyAmericansaretryingtoloseweightbecause.

A.theywanttolookattractiveB.theyaremisledbydoctors

C.theywanttokeepfitD.bothAandC

13.Thefiguresgiveninthesecondparagraphsuggestthat.

A.AmericansaredependentoncarsB.carsconsumealotofmoney

C.AmericansneedloseweightD.excessoffatcanbeasourceofenergy

14.Itcanbeinferredfromthelastparagraphthat.

A.dietbooksarenotalwayseffectiveB.dietbooksareusuallyhelpful

C.therearelotsofwaysoflosingweightD.bookstoresarekeepingtheirpromises

15.Itcanbeconcludedfromthepassagethat.

A.peoplethinktoomuchoftheirappearance

B.thereisnotasurewayoflosingweightasyet

C.surgeryisthefastestwayoflosingweight

D.goingondietisasafewayoflosingweight

PartVWriting

Directions:Forthispart,youareallowed30minutestowriteacompositiononthetopic:KeepingFit.Youshouldwriteatleast100—120wordsandyoushouldbaseyourcompositionontheoutline(giveninChinese)below:

1、保持健康的重要性;

2、保持健康的有效途径;

3、我的做法。

Thecountry’schiefexportsarecoal,carsandcottongoods,cars_____themostimportantofthese.

A、havebeen
B、are
C、being
D、arebeing

“Whatcoursesareyougoingtodonextsemester”

“Idon’tknow.Butit’sabouttime_____onsomething.”

A、I’ddecide
B、Idecided
C、Idecide
D、I’mdeciding
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