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如图,平面内的两个单位向量,,它们的夹角是60°,与、向量的夹角都为30°,且=,若,则λ+μ值为( )
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高三下学期数学《》真题及答案
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2018年·大庆一模若是夹角为60°的两个单位向量则向量=的夹角为
30°
60°
90°
120°
向量概念下列命题中正确的是
若两个向量相等,则它们的起点和终点分别重合
模相等的两个平行向量是相等向量
若
和
都是单位向量,则
=
两个相等向量的模相等
已知两个单位向量ab的夹角为60°c=ta+1-tb.若b·c=0则实数t=.
已知两个单位向量a和b的夹角为135°则当|a+λb|>1时λ的取值范围是________.
若两个单位向量ab的夹角为1200则|a–xb|xR的最小值是_______.
已知a是平面内的单位向量若向量b满足b・a-b=0则|b|的取值范围是
已知是夹角为的两个单位向量则
已知向量是同一平面内的三个向量其中是夹角为60°的两个单位向量若向量满足=﹣5则的最小值为.
已知e1e2是夹角为60°的两个单位向量a=3e1-2e2b=2e1-3e2.1求a·b2求a+b与
已知是夹角为60°的两个单位向量的夹角.
已知a与b为两个不共线的单位向量k为实数若向量a+b与向量ka-b垂直则k=__________
已知是夹角为的两个单位向量若向量则________.
下列说法中正确的是
若两个向量相等,则它们的起点和终点分别重合
模相等的两个平行向量是相等向量
若
和
都是单位向量, 则
=
.零向量与其它向量都共线
给出下列命题①空间中两直线的夹角就是它们的方向向量的夹角②相互平行的向量一定共面共面的向量也一定相互
0
1
2
3
设mn是两个单位向量向量a=m-2n且a=21则mn的夹角为.
已知两个单位向量ab的夹角为60°c=ta+1-tb若b·c=0则t=_____.
已知两个单位向量ab的夹角为60°c=ta+1-tb.若b·c=0则t=________.
下列关于单位向量与零向量的叙述正确的是
零向量是没有方向的向量,两个单位向量的模相等
零向量的方向是任意的,所有单位向量都相等
零向量的长度为
0
,单位向量不一定是相等向量
零向量只有一个方向,模相等的单位向量的方向不一定相同
已知e1e2是夹角为60°的两个单位向量若a=e1+e2b=-4e1+2e2则a与b的夹角为
30°
60°
120°
150°
已知a与b为两个不共线的单位向量k为实数若向量a+b与向量ka-b垂直则k=.
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Themorningafteraneveningflightwithmythenthree﹣year﹣olddaughterIcouldn'twaittogethertoschool.Iwastiredfromtheangerandherinabilitytocommunicatebecauseofherslowedlanguagedevelopment. AsIaccompaniedherintothecarIfeltdesperate.Nothingwasrightwithourworld.ShehadbeenbornaroundthesametimethenationwaswitnessingthebirthofanotherGreatRecession经济萧条.Myjobandmyhousehadbeenvictims.Thenthishappened.Mychild'slanguagedelaywasidentifiedbutdoctorsstruggledtoproperlydiagnosisher.Ifeltlikewebothneededtoberescued. IreturnedthatafternoonasdisenchantedwiththelittlegirlIlovedaswhenIleft. Walkingslowlytowardtheschool'splaygroundgateIfoundherpreschoolteacherracingtogreetme. Youshouldhaveseenhertoday!Hisbreathywordsweresupportedbyexcitement.Ididn'tinterrupt.Seethatclimber.Hepointedtoapieceofwoodenplaygroundequipmentthatlookedlikearockwall.Inodded.WelleverydaysinceshestartedschoolShe'stiredandfailedtomakeittothetop.Hetookabreath.Andtodayshemadeit. Heexpressedhisjoyjustlikehe'dwitnessedherconquering征服MountEverestShecheeredandcelebrated!Iwishl'drecordedit..Hiswordscomfortedme.Mydaughterhadconqueredhermountain.AssherantowardmeIrecognizedsomethingIhadn'tbefore.Isawherperseverance.Isawherstrength.Isawahero. EverydaygreatnesscelebratesordinarypeoplewhodounusualthingsinbigandsmallwaysshowingcouragekindnessloveandselflessnessWeencourageyoutoclickthesebriefaccountsandinviteyoutoshareyourownstoryinourcommunity. 1Whywastheauthor'sdaughterrushedtoschool? A.Themotherwasbusywithherworkasadoctor B.Themotherhadafightwiththedaughterlastnight. C.Themotherbrokedownwhendealingwithherdaughter. D.TheyhadtosellandleavetheirhouseduetoGreatRecession. 2Whichofthefollowingbestexplainsdisenchantedunderlinedinparagraph3? A.Disturbed. B.Dissatisfied C.Distrusted D.Disappointed. 3Whatmadethelittlegirl'spreschoolteacherfeelexcited? A.ThatshesucceededinconqueringMountEverest. B.Thatshemanagedtoclimbupthewoodenclimber. C.Thatshegotthefirstplaceintheschoolsportsmeeting D.Thatshedevelopedtheabilitytocommunicatenormally. 4Whereisthetextprobablytakenfrom? A.Ontheradio. B.Fromamagazine. C.Fromaschoolpaper D.OntheInternet
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假如你是某国际学校的学生李华你最近使用了一本XX英英词典感觉非常实用请你利用班会时间向同学们推荐它.内容要点如下 1.特色如词汇量用法例句等方面 2.使用心得. 注意1.词数100左右 2.可以适当增加细节以使行文连贯 3.开头和结尾已经给出不计入总词数. Helloeveryone!
WhenGlenKrugerpickedasmallcatfromananimalshelterhedidnotexpectmuch.Yetrightfromthestarteightyearsagotherewasanuncommonconnectionbetweenhimandthesmallblackcat.He1herInky. Igrewuponahundred﹣acrefarmandhadonlycats2playmatesKrugertheseventy﹣year﹣oldmansays.Myhearingwasdamagedbythe3offarmequipmentsoIlearnedtoconnectwith4.Theyreacttowhattheyseeandwhatyoudo. Inkywasagentlecat5thehousewithfiveothercats.ButonaJanuarynightin2009Inkydid6thatwouldsetherapartfrom7catsforever. Krugerhadgonedowntothebasementto8thewoodstoveforthenight.Whenhewasfinishedhe9tothetopofthestairsandreachedtoturnoffthelights.Indoingsoheslippedand10hisbackagainstanoldshelf.TheheavyshelfcamecrashingdownandsentKrugerdownthestairs. 11inapoolofbloodonthebasementfloorKrugerfelt12goingintoshock休克.Heshoutedforhelp13hiswifeBrendawasasleepintheirbedroomattheoppositeendofthehouse.14KrugernoticedInkywatchingfromthetopofthestairs. GogetBrendaKrugersaidtoInky. Inky15tothebedroomdoorandscratched16untilBrendaopenedit.ThenInkyledhertothe17.Brendafoundherhusband18thestairsandcalled911.Krugerwasrushedtothehospital.Ispentsixmonths19theresaysKruger.AlthoughIbecamelameIwasblessed.SincetheaccidentInkyhas20leftKruger'sside. 1A.gave B.named C.chose D.remembered 2A.like B.among C.except D.as 3A.sound B.noise C.alarm D.voice 4A.farmers B.friends C.animals D.neighbors 5A.visiting B.sharing C.dividing D.discovering 6A.anything B.nothing C.something D.everything 7A.familiar B.ordinary C.lovely D.outstanding 8A.shutoff B.shutout C.shutdown D.shutup 9A.marched B.flew C.struggled D.climbed 10A.hit B.bent C.shook D.pulled 11A.Falling B.Appearing C.Lying D.Thinking 12A.it B.himself C.him D.itself 13A.and B.or C.but D.so 14A.Then B.Otherwise C.Thus D.Rather 15A.ran B.walked C.returned D.withdrew 16A.rapidly B.suddenly C.madly D.urgently 17A.bedroom B.yard C.basement D.house 18A.atthebottomof B.inthemiddleof C.atthetopof D.inthefrontof 19A.regretting B.resting C.relaxing D.recovering 20A.ever B.never C.still D.already
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某DNA上的W基因发生突变导致合成的mRNA上一个碱基C变成A.下列叙述错误的是
新一代基因编辑CRISPR/Cas9术的实质是用特殊的引导序列sgRNA将Cas9酶﹣“基因剪刀”精准定位到所需切割的基因上然后进行编辑.科研人员设想利用新一代基因编辑技术来预防艾滋病.回答下列问题 1动物细胞中没有编码Cas9酶的基因可通过构建用法将其导入受体细胞最终表达出Cas9酶. 2CCR5蛋白是HIV病毒入侵机体细胞的主要辅助受体之一HIV通过识别膜通道蛋白CCR5侵入宿主细胞.为有效阻止HIV侵染新分化生成的T淋巴细胞科研人员将sgRNA序列导入骨髓细胞中以构建sgRNA﹣Cas9酶复合体.Cas9酶可以催化键断裂以实现对DNA序列的定向切割.设计sgRNA序列需要根据的核苷酸序列原因是. 3为检测T淋巴细胞的CCR5基因是否成功被编辑采用技术检测是否含有CCR5基因还需要对蛋白进行检测.
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阅读下面短文根据所给情节进行续写使之构成一个完整的故事. WhenIwastenyearsoldIlivedwithmyfamilyinasmallhouseinruralSouthJersey.IoftenaccompaniedmymothertotheA&Ptobuygroceries.WithoutacarwewalkedandIwouldhelphercarrythebags. Mymotherhadtoshopeverycarefullyasshewasawaitressandhersalarybarelysustained勉强维持us.OnedaywhileshewasweighingpricesapromotionaldisplayfortheWorldBookEncyclopediacaughtmyeye.Thevolumeswerebeautifullycream﹣colored.VolumeIwasninety﹣ninecentswithaten﹣dollarpurchase. AllIcouldthinkofwhileshoppingwasthebook.Istoodattheregister收银台withmymotherholdingmybreathasthecashierranguptheitems.Itcametooverelevendollars.Mymotherproducedafivesomesinglesandahandfulofchange.AsshewascountingoutthemoneyIsomehowfoundthecouragetoaskfortheencyclopedia百科全书.Couldwegetone?Isaidshowingherthedisplay.It'sonlyninety﹣ninecents. Ididnotunderstandmymother'sincreasinganxietyshedidnothaveenoughchangeandhadtosacrificealargecanofpeastopaytheamount.NotnowPatriciashesaidsternly.Todayisnotagoodday.Ipackedthegroceriesandfollowedherhomeupset. ThenextSaturdaymymothergavemeadollarandsentmetotheA&Palone.Twoquartsofmilkandaloafofbread﹣﹣﹣that'swhatadollarin1957.IwentstraighttotheWorldBookdisplay.TherewasonlyonefirstvolumeleftwhichIplacedinmycart购物车.Ididn'tneedacartbuttookonesoIcouldreadasIwentupanddowntheaisles.AlotoftimewentbyandIknewIhadtoleavebutIcouldn'tbeartopartwiththebook.WithnodetectiveinsightIimpulsively冲动地putitinsidemyshirtandzippedupmyjacket.IwasatallskinnykidandIamcertaintheshapeofthebookwasobvious. Paragraph1MyheartbeatingrapidlyIheadedfortheregister. Paragraph2Backhome.ItoldmymotherwhatIhadpromisedthedetective.
PrepareYourselfforaBetterTOEFLScore TheTOEFListhemostwidelyusedlameassessmentexamforAmericancollegesoruniversities.ManyforeignstudentsworryabouttakingtheTOEFLbecauseitisessentialtomeettheirgoals.1Butalowtestscorewilllimittheirchoicesforfinancialaidandadmissiontotopschools.SohowtoprepareyourselfforabetterTOEFLscore? Whatwillyoufocuson? PlanwhenyouwilltaketheTOEFL.Ifpossibleregistertotakethetestevenifthedateisseveralmonthsfromnow.Thiswillgiveyouagoodreasontostudy.Takeasampletestonlineorfromatestpreparationbooktofindoutwhereyouneedtoimprovethemost.2Thiswillhelpyoutoplanyourstudiestodeveloptheskillsyouneedtogetabetterscore. 3 TheEducationalTestingServicewebsitehasafreeonlinecoursetohelpyoupreparefortheTOEFL.Therearealsosamplepreparationquestions.ApartfromansweringthosequestionstrytosurroundyourselfwithEnglish.ListentostoriesonVOA'sLearningEnglishwebsite.WatchmovieswhereEnglishisspoken.ReadEnglish﹣languagenewspaperstokeepupwithnewwordsthatrelatetocurrenteventsandtechnology. Whenwillyoustudy? 4Butifyourpracticetestscoreismorethan20pointsbelowyourgoalyoumayneedtoimproveyouroverallEnglishabilityandthatmaytakeyears.Togetagoodscoreyouneedtosetasidetimetostudysetgoalsandmeasureyourprogress. TherealgoalofthetestistomeasurehowwellastudentcancommunicateinanEnglish﹣speakingclassroom.5 A.Howwillyoustudy? B.Donotdependoninformaladviceortricks. C.Goodmarksonthetestwillopenmanydoors. D.Doyoudowellinreadingbutnotsowellinlistening? E.Exportssaythatyoushouldstudyforatleasttwomonthsbeforetakingthetest. F.ExposeyourselftoEnglishonadailybasisandimprovementissuretofollow G.ATOEFLscoremaybenecessarytogetastudentvisatoanEnglish﹣speakingcountry.
阅读下面短文根据其内容写一篇60词左右的内容概要. Paperlessofficewasfirstcoinedin1975.Fourdecadeslaterwe'restillchasingthepaperlessofficedream.Takethefinancialindustryforexample﹣itisoneoftheslowerindustriestohugdigitaltransformation.Manyfinancialinstitutionstodaystillsendouttradeconformationsbymail.Icantellyoufromfirsthandexperiencethatgoingpaperlessisbynomeansimpossible.TheCentricDigitalofficeisapaperlessworkenvironmentwherealltheofficeoperationsgodigitalwhichhasamazedourbusinesspartners. Actuallycompaniesneedtostressthebenefitsofadigitalcultureforcommunications.Goingpaperlesscansavetimeandmoney.Youcouldsaygoodbyetocostlyrepairsofficesupplyorderswastedemployeetimeandsoon.Besidesforbiddingpaperintheofficeforcesinformationtobe100%digitalwhereyoucanmakeendlessamountsofbackups备份whicheasilyincreasetransparency透明.Nottomentiontoptalentswanttoworkfordigitalcompanies. Youmightthinkthesecrettoapaperlesscompanyispurelytechnology.Wellnotreally.ThankstoproductslikeiPadssmartphonesandcloudservicestheabilitytogopaperlessishighlyaccessible.Yetevenwithallthistechnologycompaniescontinuetorelyonpaper.It'snotbecausetheydon'thaveaccesstothetechnologybutbecausethey'relackingthepoliticsorganizationalstructureandstrongdesiretochange.Inordertogopaperlesscompaniesneedtochangethewaytheythinkandoperate.Thedecisionneedstobemadeandcriedoutandeveryoneneedstoworktogethertomakeit. Yesthepaperlessofficehasbeenaverylongtimeinthemaking一butitnolongerhastobe.Withnumerousamountsofsoftwareservicesappsandtechnologyavailabletodaytheonlythingweneedtodoistomakethedecisiontogopaperlessandseeitthrough.
Forsomepeoplewalkingorrunningoutdoorsisaeatwaytoworkout.Whatmaynotbesopleasantisseeingtrashallovertheground.Wellsomepeoplearedoingsomethingaboutit.Theyareplogging! PloggingbeganinSweden.ThenamecombinetheSwedishwordplockawhichmeanstopickupandthewordjoggingwhichmeanstorunslowly.ASwedishmannamedErikstartedthemovementin2016.OntheWorldEnvironmentDaywebsiteEriksaysthathemovedtoStockholmfromasmallcommunityinnorthernSweden.Eachdayhewouldridehisbiketowork.Concernedabouttheamountoftrashandlitterhesaweachdayonhiswaytoworkhetookmattersintohisownhands. PloggingbythattermmayhaveofficiallybeguninSweden.Butmanypeoplewhoexerciseoutdoorshavebeendoingthisforyears.TakeJeffHorowitzforexample.HeisapersonaltrainerinWashingtonD.C.Heoftenpicksuptrashwhilerunningoutside.Heevenasturneditintoagamehewilltrytopickupthetrashwithoutstopping.Ididn'tknowitwasathingreally.Thisisjustmypersonalethics道德标准whereIgoforarunandifIhappentoseeapieceofgarbagelyingaroundandit'swithinreach﹣﹣﹣itisakindofalittletestformetoseeifIcangrabitandthrowitinanearrashcanwithoutstopping.AndthatwayIthinkitgivesmealittleexerciseandalittlefocusformyrun.Andithelpscleanuptheneighborhoodheannounced. Todayloggingisanofficialactivityonethatisbecomingincreasinglypopular.Citiesaroundtheworldnowholdloggingevents.Iwouldjusthopepeoplewouldthinktwicebeforedroppingagarbageontheround.Wehavecontainers…seemsoneveryblock.Soit'seasytoputyourgarbageinthetrashcans.Ijustthinkpeopleshouldthinkaboutitalittlebitmore.Idohopeonedaytherewillnotbeaneedforlogging.saidaninterviewee. 1Whichofthefollowingcanreplacetheunderlinedphrasetookmattersintohisownhands? A.calledonpeopletojoinhim B.appealedtopeopletogogreen. C.begantopickupthetrash. D.hadthecollectedtrashrecycled. 2LikeJeffHorowitzloggingtomanypeoplehasbecomeaanact. A.automatic. B.irresistible. C.arbitrary D.temporary 3WhatistheideathatLoggingeventsaremeanttopromote? A.loggingistrulybeneficial B.Trashcansshouldbewithinreach C.Litteringisnotacceptable. D.Communitiesshouldbekeptclean. 4Whatcanbeasuitabletitleforthepassage? A.NewExerciseEnjoysunbelievablepopularity B.NewExerciseTrendAlsoHelpsEnvironment C.Plogging﹣aFashionableWaytoclearwaste D.Plogging﹣anExerciseOriginatinginSweden
实施乡村振兴战略是建设美丽中国的关键我国是世界第一的鹅养殖大国约占世界出栏量的90%快速识别刚孵化的雏鹅性别对规模化养殖至关重要.某白鹅品种甲刚孵化出来的维鹅绒羽通常呈黄色或浅褐色饲养9个月后雏鹅性成熟绒羽退尽换上新羽羽色都是白色.科学家在繁育过程中选择成年10月龄公鹅40只母鹅200只进行混群饲养随机交配孵化获得1个批次的雏鹅G1观察雏鹅的绒羽和性别统计结果如下.请回答 1同一只鹅的雏鹅的绒羽羽色与成体的羽色有很大差异这说明控制羽色的基因羽毛的差异是基因选择性表达的结果. 2据表推测白鹅品种甲的雏鹅绒羽颜色为显性性状推测绒羽颜色遗传最可能是伴性遗传的理由是. 3为进一步确定白鹅品种甲的绒羽颜色的遗传方式从该批次白鹅G1中选取雏期绒羽颜色为的公鹅和的母鹅进行杂交实验通过子一代F1的绒羽色和性别进行确认若F1中则说明控制绒羽色的基因只在Z染色体上且能快速分辨雏鹅性别. 4若以上分析正确第1批次G1的母鹅中浅褐色绒羽的基因频率是推算依据是.
我国科技人员创造了浮床生态工艺法净化生活污水含有机物和无机物在水域中固定浮床上种植特殊的水生半水生植物以吸收水中的氮磷等元素.回答下列问题 1流经该水域生态系统的总能量是. 2生活污水流入水域中通过物理沉降化学分解和使污水得到净化.若流入该水域的生活污水过量则会导致生态系统遭到破坏原因是. 3浮床生态工艺法还能抑制藻类的繁殖防止“水华”发生原因是.答两点即可
Greenlifestyleisbecomingincreasinglypopularnowadays.1Youdon'thavetocompletelychangethewayyouliveyoujustneedtomakeafewsmallchanges.Fromrecyclingtogreenshoppingeachsmallchangeyoumakecanreallymakeadifference.Herearesomebenefitsoflivingagreenlifestyle. Helptheenvironment.Bybeingenergy﹣efficientandusinggreenproductsyoucanreduceyourinfluenceontheenvironment.Youcanhelppreserveournaturalresourcesandreducepollution.2.Itdoesfeelveryrewardingwhenyoustartmakingpositivechangesandfeelingasthoughyou'remakingadifferencetosuchanimportantcause. Liveahealthierlife.Ifmorepeoplecommittobeinggreenthenwe'llbeabletoliveinahealthierenvironmentwithlesspollutionandbetterairquality.You'realsomorelikelytomakebetterchoiceswhenitcomestofoodandyoucouldfindyourselfleadingamoreactivelifestyle.Growingyourownvegetablesisaveryhealthywaytoliveaswellasbuyinggreennaturalfoods.Cyclingandwalkingtoplacesinsteadofusingyourcarcanhaveabiginfluence.3. Savemoneyonbills.Youcangreatlyreduceyourenergybillsbyusingenergyefficientequipment.4Recyclingisalsoanothergreatwayofsavingmoneyandhelpingtheenvironment. 5.Onceyouhavepickedupsomegoodtipsandgreenlivingtechniquesyoucanpassthemontootherpeople.Youcanalsotalktofriendsandfamilyandinformthemofthebenefitsofgoinggreen.Yourchildrenwillgrowupunderstandingtheimportanceoflivingagreenlifestyleandwilllearnhowtoreducetheirinfluenceontheenvironment. A.Educateothers. B.Meetlike﹣mindedpeople. C.Itwillalsomakeyoumuchfitter. D.Therearelotsofwaysofsavingmoney. E.Youcanalsodoyourpartforwildlifeconservation. F.Livingagreenlifestyleisn'tashardasitmightseem. G.Ifyougrowyourownproduceyouneedn'tspendasmuchonfood.
为了研究水生生物对富营养化水体中磷的去除作用研究人员从某城市内河中取水样分别设置水葫芦鲢鱼“水葫芦+鲢鱼”等不同处理组进行实验分别取样检测水体中总磷浓度变化结果如图.下列相关叙述错误的是
下列有关生物学实验操作正确的有 ①探究温度对酶活性的影响可选择过氧化氢溶液作底物 ②在电子显微镜下拍摄到的叶绿体的结构照片属于物理模型 ③在花生子叶薄片上滴加苏丹III染液发现满视野都呈现橘黄色于是滴1﹣2滴50%酒精洗去浮色 ④在模拟细胞大小与物质运输的关系时琼脂块表面积和体积之比是自变量氢氧化钠扩散速度是因变量 ⑤用无水乙醇对绿叶中的色素进行提取和分离溶解度越大的色素在滤纸条上扩散速度越快 ⑥在观察细胞内DNA和RNA分布的实验中可使用酒精来改变细胞膜通透性加速染色剂进入细胞.
7.5分Peopletendtoacceptgroup'sstandardsofbehaviorandthinkinginagroupwork.Manyillustrations例证couldbegivenofthisfromeverydaylifebutwhatisofparticularinteresttopsychologistsishowmuchpeople'sjudgmentsandopinionscanbechangedasaresultofgrouppressure.Aschandothersnoticedthatpeopleinagroupwillagreetostatementsthatarecontrarytotheevidenceoftheirsenses.Itwouldbeamistaketothinkthatonlyparticularchangeablepeoplearechosentotakepartinexperimentsofthistype.Usuallyhighlyintelligentandindependentpeopleareused. Inatypicalexperimentthisiswhatmayhappen.Theexperimenterasksforvolunteerstojoinagroupwhichisinvestigatingvisualsense.Theparticipantsarenotthereforeawareoftherealpurposeoftheexperiment.Eachvolunteeristakentoaroomwherehefindsagroupofaboutsevenpeoplewhoarecooperatingwiththeexperimenter.Thegroupisshownastandardcardwhichcontainsasingleline.Theyarethenaskedtolookatasecondcard.Thishasthreelinesonit.Oneisobviouslylongerthanthelineonthefirstcardoneisshorterandonethesamelength.Theyhavetosaywhichlineonthesecondcardisthesamelengthasthelineonthestandardcard.Theothermembersofthegroupanswerfirstbuttwhatthevolunteerdoesnotknowisthattheyhavebeentoldtopickoneofthewronglines.Whenhis turncomesheisfacedwiththeconsistentopinionoftherestofthegroup﹣alltheothershavechosenlineAbuthequiteclearlyseeslineBascorrect. Whatwillhedo?AccordingtoAschmorethanhalfofthevictimschosenwillchangetheiropinion.Whatisequallysurprisingisthatwheninterviewedabouttheiranswersmostexplainedthattheyknowthegroupchoicewasincorrectbutthattheyyieldtothepressureofthegroupbecausetheythoughttheymustbesufferingfromanopticalillusion视觉假象orbecausetheywereafraidofbeingdifferent. 1Thepsychologistsareespeciallyinterestedin. A.theevidenceoftheexperiment B.thechangesintheattitudesofpeople C.thedifferenceinpeople'sbehavior D.thedegreeofchangesofpeople'sopinions 2Whymorethanhalfofthevictimschangestheiropinionsintheexperiment? A.Becausetheyhadbeentoldabouttheanswer. B.Becausethoughtthegroupchoicewascorrect. C.Becausetheysubmittedtothegrouppressure. D.Becausetheireyesweresufferingfromillusion. 3Thepurposeoftheauthorinwritingthispassageisto. A.illustratetheinfluenceofgrouppressureonindividuals B.encouragepeopletoactagainstanygroup'sopinion C.invitemorevolunteerstojoininAsch'sexperiment D.tellthereadershowtoperformpsychologicalexperiment
短文中共有10处错误错误涉及一个单词的增加删除或修改. 增加在缺词处加一个漏词符号∧并在此符号下面写出该加的词. 删除把多余的词用斜线\划掉. 修改在错的词下划一横线并在该词的下面写出修改后的词. 注意1.每处错误及其修改均仅限一词 2.只允许修改10处多者从第11处起不计分. NowletmeintroduceourEnglishpapertoyou.Onmyopinionthepaperisveryimportancetoourstudy.WecanimproveourEnglishespeciallywritingEnglishbyreadingit.Secondlyit'saveryinterestingtoreaditwhichmadeourafter﹣classtimemeaningfulandcolorful.What'smorethereisalotofcolumnsinourpapersuchSchoolNewsTeachers'AdviceandStudents'Voice.Itnotonlymakesuslearntheimportanteventsandalsohelpsuscommunicatingwithteachers.Wecantaketheadvicesfromourteachers.InawordIlikeourEnglishpaperverymuch.
胰腺是哺乳动物重要器官科学家用胰腺进行科学实验探究其重要功能.请回答 1斯他林和贝利斯剪取狗小肠并刮下黏膜将黏膜与稀盐酸混合加砂子磨碎制成提取液发现提取液可促进胰腺分泌胰液.该实验验证的假设是. 2胰腺中大部分是胰腺细胞其间散布着胰岛胰岛A细胞和胰岛B细胞分布其中其分布方式为填“胰岛A细胞胰岛B细胞分别集群形成胰岛”/“胰岛A细胞胰岛B细胞及其他细胞混合集群形成胰岛”. 3胰腺中分泌的胰高血糖素与肝细胞膜上的受体结合后调节糖代谢过程这反映了细胞膜具有的功能.人体内需要胰腺源源不断地分泌胰岛素以维持激素含量动态平衡的原因是. 4科学家在豚鼠胰腺腺泡细胞中注射3H标记的亮氨酸并破坏了腺泡细胞中全部的高尔基体检测放射性的聚集和转移情况.结果发现放射性只在细胞内进行转移但却未出现在细胞外这表明.
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