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已知正项数列{an}的前n项和为Sn,满足2=an,则﹣+﹣+……+(﹣1)51( )
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高三下学期数学《》真题及答案
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假定英语课上老师要求同桌之间交换修改作文请你修改你同桌写的以下作文.文中共有10处语言错误每句中最多有两处.每处错误仅涉及一个单词的增加删除或修改. 增加在缺词处加一个漏字符号∧并在其下面写出该加的词. 删除把多余的用斜线划掉. 修改在错的词下划一横线并在该词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. Inmyschoolwehaveourowntalentshoweveryyearthathasbeenatraditionfor15years.Thisyearourschoolwasheldoneasscheduled.Agreatmanystudentstookactivepartinit.IdecidedtoplaytheviolinwithapartnernamingJuliawhoplayedthepianoalongforme.Wehadpracticedmanytimebeforethetalentshowstarted. Everyonewatchedtheshowexcited.JuliaandIdidagoodjob.Othersstudentssanganddancedhappily.Thetalentshowhelpedusrelaxbutenrichedourschoollife.Weallenjoyedthemverymuch.
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Robotsarenowbeingemployednotjustfordangeroustaskssuchasdiscoveringminesorrescuingpeopleindisasters.Theyarealsofindingapplicationashouseholdhelpsandasnursingassistants.Asincreasingnumbersofmachinesequippedwiththelatestartificialintelligencetakeonagrowingvarietyofspecializedandeverydaytasksthequestionofhowpeopleseethemandbehavetowardsthembecomesevermoreurgent. AteamledbySariNijssenofRadboudUniversityandMarkusPaulusProfessorofDevelopmentalPsychologyatLudwig﹣Maximilians﹣UniversitaetLMUhavecarriedoutastudytodeterminethedegreetowhichpeopleshowconcernforrobotsandbehavetowardsthembasedonmoralprinciples. AccordingtoSariNijssenthestudysetouttoanswerthefollowingquestionUnderwhatcircumstanceswouldadultsbewillingtosacrificerobotstosavehumanlives?Theparticipantswerefacedwithahypothetical假设的moraldilemmaWouldtheybepreparedtoputasinglepersonatriskinordertosaveagroupofinjuredpersons?Inthesituationspresentedtheintendedvictimwaseitherahumanahumanoidrobotthathadbeenhumanized人性化的tovariousdegreesorarobotthatwasclearlyrecognizableasamachine. Thestudysuggestedthatthemoretherobotwashumanizedthelesslikelyparticipantsweretosacrificeit.Situationsthatincludedvividstoriesinwhichtherobotwasdescribedasamercifulbeingorasacreaturewithitsownunderstandingsexperiencesandthou^itsweremorelikelytostopthestudyparticipantsfromsacrificingitintheinterestsofanonymous无名的humans. ThisresultindicatesthatourstudygroupattachedacertainmoralstatustotherobotsaysPau﹣lus.Onepossiblesuggestionofthisfindingisthatattemptstohumanizerobotsshouldnotgotoofar.Sucheffortscouldcomeintoconflictwiththeirintendedfunction﹣tobeofhelptous. 1Whathasbecomeaconcernaboutrobots? A.Howtohumanizethem. B.Howtotreattheminlife. C.Howtousethemeffectively. D.Howtofindmoreapplications. 2Inthestudytheparticipantsprobablyhavetodecide. A.whentosacrificearobot B.wheretoexperiencerisks C.whichrobottoworkwith D.whatrobotsshouldbelike 3WhatcanbeinferredfromPaulus'words? A.Humanizedrobotsofferlesshelptopeople. B.Humanizingrobotstoomuchmaybeimproper. C.Certainmoralstatusshouldbeattachedtorobots. D.Conflictsoftenhappenbetweenhumansandrobots. 4Whichofthefollowingwouldbethebesttitleforthetext? A.RobotsAMustforFuture B.HumanizedRobotsANewTrend C.RobotSavedPeopleTaketheHit D.HumanizedRobotsReplaceHuman
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Inacleanclinicalroommybestfriendwasdyinginmyarms.Hiseyesdarkbrownandtrustingwouldsoon1forever.HeartbrokenIsaidFlashyou2somuchhappinesstome.Iwilldosomethinggoodasa3. Flashcameintomy4whenIwasnine.Fromthemomentrayparentsbroughtthiscutedoghomehe5myfamilywithjoy. Then6happened.MymumwasdiagnosedwithbreastcancerwhenIwas11.Thenmygrandmawhowasmy7passedaway.MysisterdevelopedCrohn'sDiseaseandwhilebeingtested8aheartattack.Iwasbeingbulliedatschoolandstartedto9classesandavoidseeingpeople. Flashsoongaveroeallthe10hecouldoffer.ThereweretimeswhenIfelttherewasno11butapairofbrowneyesandlovingfacewouldsomehowcaseme.Iknewhewas12thereforme.Iknewheunderstood. Nowafter15yearsFlashwas13.Ithoughtdoingcharityworkwasthebestrewardforhim.I14inanon﹣profitorganizationinSouthamptonandcontributedabout3500hoursto15hildrenwithspecialneedswhichcompletelychangedmylife.Ilearnedtolovethe16Ihadbeenonandevenacceptthe17bits. IstillmissFlash.Itwashimthathadsomehow18metohelpingothers.Flash'sdeathwasoneofthe19momentsofmylife.Butitalsoaninspiringmomentthat20whoIwas﹣inthebestpossibleway﹣forever. 1A.open B.close C.shine D.fade 2A.brought B.told C.saved D.owed 3A.relief B.chance C.bonus D.reward 4A.mind B.room C.world D.power 5A.helped B.filled C.protected D.decorated 6A.disasters B.stories C.wonders D.mistakes 7A.burden B.trouble C.strength D.challenge 8A.caused B.noticed C.fought D.suffered 9A.skip B.give C.take D.enjoy 10A.comment B.comfort C.expectation D.relaxation 11A.hope B.time C.money D.use 12A.frequently B.sometimes C.hardly D.always 13A.aging B.gone C.missing D.deserted 14A.searched B.competed C.volunteered D.performed 15A.attendingto B.meetingwith C.talkingabout D.bringingup 16A.earth B.journey C.holiday D.street 17A.fantastic B.absurd C.hard D.pleasant 18A.led B.forced C.trained D.persuaded 19A.fullest B.craziest C.tiniest D.saddest 20A.explained B.transformed C.admitted D.described
Ifyoufeelsickoruncomfortableyoumightseekoutadoctor.Butwhattodoifyoudon'tquiteknowwhereyoufitintothisworldandyou'retiredofcarryingthatburdenalone? Iansweredstrangers'questionsonlifepuzzlesattheentrancetotheNewYorkCitysubwayat57thand8th.Agroupofstrangershadstoppedbybecausetheywerecarryingaroundsomedeepmeaningfulquestionsthathadlonggoneunansweredlikewhycan'tIbehappierinmylife? AndthenIspottedherwhowouldbemytoughestquestioneroftheday.Shewasabout6yearsoldandheldhermother'shandasshecraned伸长脖子hernecktostareatas.Hermotherstoppedbutthegirlhesitated.It'sOKIoffered.Doyouhaveaquestion?Thegirlsmiledathermotherthenletgoofherhandtowalkovertowardsus.ShelookedmedeadintheeyeandsaidHowdoIknowI'mreal? SuddenlyIwasbackingraduateschool.ShouldItalkabouttheFrenchphilosopherReneDescartestoproveourexistencewiththephraseIthinkthereforeIam?OrmenlionEnglishphilosopherG. Mooreandhisfamousuhereisonehandhereistheothertoprovetheexistenceoftheexternalworld?Butthentheanswercametome.Irememberedthatthemostimportantpartofphilosophywasfeedingoursenseofwonder.CloseyoureyesIsaid.Shedid.Welldidyoudisappear?Shesmiledandshookherheadthenopenedhereyes.Congratulationsyou'rereal. Shegrinned露齿而笑broadlyandwalkedovertohermotherwholookedbackatusandsmiled. 1Whydidtheauthorshowupattheentranceofthesubway? A.Totakethesubway. B.Tolookforstrangers'help. C.Toofferadviceonlifepuzzles. D.Tohelpstrangerscarrytheirbags. 2Whatmadethelittlegirlstareattheauthor? A.Curiosity. B.Horror. C.Excitement. D.Nervousness. 3Howdidthegirlfindtheanswer? A.Byhearingastory. B.Bylearningphilosophy. C.Byreferringtoothers'words. D.Byhavingarealexperience. 4Whichofthefollowingcanbestdescribetheauthor? A.Strictandsmart. B.Honestandbrave. C.Cleverandhelpful. D.Humorousandsociable.
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WhenIfirstcametoUKfromChinaat6Ienteredthefirstgrade.1.Isawchildrenthrowtheirleftoverfoodintothelargetrashcans﹣fromhalf﹣eatenpizzastountouchedburgers.Iwatchedthempourtheirmilkintoawhitebucket.InChinathiswasahugeno﹣noinschool.Wehadtofinisheverything. Onedaymyfirstgradeteacherannouncedthatwewouldbehavingapartyandeveryonewastoldtobringsomethingfromtheircountry.2.Mymomstayedupafterherlongdayofworkandmademanydumplings.SheputtheminthefridgeandwokeupearlyinthemorningtosteamthemandfrythemsotheywouldtasteextrafreshwhenIbroughtthemtoschool.Theysmelledgreatandlookedgoldenbrownaftertheywerecooked. Iwassoexcitedtosharethesewithmyclassandteachers.Itwasplacedinthecornerofthetablenexttoalltheotherdeliciousfood.3.OneortwokidsbravelytookapieceandknewwhattheywerebecausetheyhaditwiththeirparentsataChineserestaurant.Attheendofthepartyitwascleanup.MyteacherwalkeduptomeandaskedpointingtothedumplingsWouldyouliketotakethesehome?IcarefullyrepliedNo…4.IthoughtshewasgoingtoshareitwithotherteachersbutimmediatelyafterIsaidthatshethrewallthedumplingsintothetrashandcontinuedcleaning.Iwasconfused;whatjusthappened? 5.AndtodayIstillwitnessthisfrequentlyinmyEnglishfiends.Pleaseeatallyourfoodortakeittogoorshareitorjustgetenoughsoyoudon'thavetothrowitaway.Thankyou. A.InChinanousuallymeansyes B.Igotsuperexcitedandtoldmyparents C.Itwasveryimpolitetotakeyourgifthome D.ThiswasthebiggestcultureshockIhaveexperienced E.WhenIgothomeIsharedtheexperiencewithmyparents F.Manykidshadthecookiesandjuicesandwerehesitanttotrythedumplings G.Ididn'tunderstandwhykidsweregettingtheirlunchfoodandnotfinishingit
Aroundtheworldmalnutrition营养不良hasbecomeaproblemthatcosts﹩3.5trillionperyearaccordingtothelatestGlobalNutritionReport1givesananalysisoffoodandnutritionissueseachyear. Althoughmostcountrieshavefallenshortintheirefforts2dealwithpoornutritionandfoodinsecuritytheUSappearstobebadlyofftrackthereportfound.Theworld's3largeeconomycontinuestosufferfromhighratesofobesitydiabetesandanemia贫血accordingtothedataandhasmorethanamillionoverweightchildren. Malnutritionisresponsibleformoreill﹣health4anyothercause.5healthconsequencesofoverweightandobesitycontributetofourmilliondeaths6globe.CorinnaHawkesdirectoroftheCenterforFoodPolicy7writeinthereport. Accordingtothestudymostcountrieshaveatleasttwoissuesrelatedtomalnutrition.Themostseriousissuesarechildrenwhoareeitheroverweightanemic8sufferfromundevelopedgrowth.Overallmalnutritioncontributestoabouthalfofallchildhooddeathstheresearchshowed.Andthose9affectmaynotbeabletogetasgoodajobastheycouldhaveiftheyhadbeenfedwell.Italsopreventsthem10beabletocontributetosocietyandtheeconomyaswellastheywouldhaveinahealthierenvironment.
假设你是李华你的英国笔友Tony即将完成学业上周他来信就是否到中国工作询问你的意见.请根据以下提示回一封电子邮件内容包括 1建议他来中国就业; 2阐述你的理由就业机会多专业受欢迎不同的文化体验等; 3承诺可以提供帮助. 注意1词数100左右开头和结尾已给出不计入总词数; 2可适当增加细节以使行文连贯. DearTony Yours LiHua
小郑同学利用手边的器材天平和砝码空玻璃瓶足够的水某种液体顺利的完成了测量“某种液体密度”的实验.下面给出的是小郑完成实验时的第一个步骤请你将实验步骤补充完整.已知水的密度为ρ水待测液体足够多 1用调节好的天平和砝码测出空玻璃瓶的质量m0并记录在表格中 2用调节好的托盘天平测量并记录在表格中 3用调节好的托盘天平测量并记录在表格中 液体密度的计算公式ρ液=.
在水平桌面上探究平面镜成像特点的实验装置与实验情景如图所示请完成下列问题 1如图甲所示在实验过程中要用透明的平板玻璃代替平面镜.如果现有5mm厚和2mm厚的两块玻璃板应选择2mm厚的玻璃板做实验其目的是减小玻璃板厚度导致的两个像而产生的重影现象对实验结果的影响. 2如图乙所示如果玻璃板没有与水平桌面竖直放置则在实验操作过程中会出现的情况是桌面上玻璃板后蜡烛无法和玻璃板前蜡烛的像重合 3如图丙所示经过三次实验在正确的实验操作过程中要分别标记像A′B′C′与物ABC相应的位置为了得到更多的实验结论接下来应该进行的实验操作是将像和物位置的对应点相连接其目的是为了判断像物连线与镜面是否垂直以及像和物到平面镜的距离相等.
顶端优势现象产生的原因是
如图是标准大气压下质量为1g的某液体的体积﹣﹣温度图以下说法正确的是
我们可以用图示的电路图测量未知电阻RX的阻值.调节电路当电压表示数U为3.0V时电流表的示数为0.3A.如果考虑到电流表的电阻值RA为0.5Ω待测电阻RX′的阻值应为Ω.
手和脚有时会磨出“水泡”.“水泡”中的液体主要是
由金属杆组成如图所示的导轨其中水平面上两平行导轨足够长且全部置于竖直向上的磁场中与倾斜放置的导轨ABCD平滑且固定连接.将一金属棒ab从倾斜导轨上一定高度由静止释放运动过程中始终与导轨垂直接触且不受摩擦因为从能量转化的角度简述理由所以ab棒在水平导轨上的运动情况是选填加速减速或匀速.
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