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如图所示,光滑固定斜面倾角θ=30°,一轻质弹簧底端固定,上端与M=3kg的物体B相连,初始时B静止,A物体质量m=1kg,在斜面上距B物体S1=10cm处由静止释放,A物体下滑过程中与B发生碰撞,...
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高三下学期物理《》真题及答案
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如图所示在倾角为30°的光滑斜面上一劲度系数为k=200N/m的轻质弹簧一端连接固定挡板C.上另一端
如图所示倾角为θ的直角斜面体固定在水平地面上其顶端固定有一轻质定滑轮轻质弹簧和轻质细绳相连一端接质量
如图所示水平轨道BC的左端与固定的光滑竖直圆轨道相切与B.点右端与一倾角为30°的光滑斜面轨道在C.
如图所示在水平地面上固定一个倾角为θ的光滑绝缘斜面斜面处于电场强度大小为E.方向沿斜面向下的匀强电场
如图所示
B.C.三球的质量均为m,轻质弹簧一端固定在斜面顶端、另一端与A.球相连,A.
间固定一个轻杆,B.
间由一轻质细线连接.倾角为θ的光滑斜面固定在地面上,弹簧、轻杆与细线均平行于斜面,初始系统处于静止状态,细线被烧断的瞬间,下列说法正确的是( ) A.B.球的受力情况未变,加速度为零 B.A.B.两个小球的加速度均沿斜面向上,大小均为
gsinθ C.A.B.之间杆的拉力大小为2mgsinθ
C.球的加速度沿斜面向下,大小为2gsinθ
如图所示光滑斜面的顶端固定一轻质弹簧一小球向右滑行并冲上固定在地面上的斜面.设物体在斜面最低点
的速度为v,压缩弹簧至C.点时弹簧最短,C.点距地面高度为h,不计小球与弹簧碰撞过程中的能量损失,则小球在C.点时弹簧的弹性势能是 ( )
A.1/2mv
2
1/2mv
2
+mgh
1/2mv
2
-mgh
mgh
如图所示在光滑斜面上有一轻质弹簧的一端固定在斜面上有一物体
沿着斜面下滑,当物体A.刚接触弹簧的一瞬间到弹簧压缩到最低点的过程中,下列说法中正确的是
A.物体的加速度将逐渐增大
物体的加速度将先增大,后减小
物体的速度将逐渐减小
物体的速度将先增大,后减小
如图所示台秤上放一光滑平板其左边固定一挡板一轻质弹簧将挡板和一条形磁铁连接起来现在磁铁上方中心偏左位
弹簧长度将变长
弹簧长度将变短
台秤读数变小
台秤读数变大
如图所示
B.C.三球的质量均为m,轻质弹簧一端固定在斜面顶端,另一端与A.球相连,A.
间固定一个轻杆,B.
间由一轻质细线连接。倾角为θ的光滑斜面固定在地面上,弹簧、轻杆与细线均平行于斜面,初始时系统处于静止状态。则在细线被烧断的瞬间,下列说法正确的是
A.B球的受力情况不变,加速度仍为零 B.A.B.两个小球的加速度均沿斜面向上,大小均为gsin θ C.A.B.之间杆的拉力大小为mgsin θ
C球的加速度沿斜面向下,大小为gsin θ
如图所示光滑水平面上静止着倾角为θ高度为H.质量为M.的光滑斜面质量为m的小球以一定的初速度从斜面底
2017河南天一大联考如图所示斜面体B.固定在水平面上物体
静置茬
上,且A.的左端连接一轻质弹簧,弹簧左端要固定在竖直挡板上.现水平左右移动挡板,A.始终在斜面体B.上静止.斜面体B.的倾角θ=30°,物体A.的质量为m,移动过程中弹簧始终处于水平压缩状态.则下列说法正确的是( )
A.A.B.之间的接触面可能是光滑的 B.弹簧弹力越大,A.B.之间的摩擦力越大
A.B.之间的摩擦力为0时,弹簧弹力为
mg
当弹簧弹力为
mg时,A.所受摩擦力大小为mg
如图所示倾角为θ的直角斜面体固定在水平地面上其顶端固定有一轻质定滑轮轻质弹簧和轻质细绳相连一端接质量
如下图所示一轻质弹簧一端固定在斜面底端光滑的小球放在另一端用沿斜面向下的外力F.压着小球使得小球静止
一直加速
匀加速运动
先加速后减速
先减速后加速
如图所示A.B.C.三球的质量均为m轻质弹簧一端固定在斜面顶端另一端与A.球相连A.B.间固定一个轻
如图所示水平轨道BC的左端与固定的光滑竖直圆轨道相切与B.点右端与一倾角为30°的光滑斜面轨道在C.
如图所示
B.C.三球的质量均为m,轻质弹簧一端固定在斜面顶端、另一端与A.球相连,A.
间固定一个轻杆,B.
间由一轻质细线连接.倾角为θ的光滑斜面固定在地面上,弹簧、轻杆与细线均平行于斜面,初始系统处于静止状态,细线被烧断的瞬间,下列说法正确的是( ) A.B.球的受力情况未变,加速度为零 B.A.B.两个小球的加速度均沿斜面向上,大小均为
gsinθ C.A.B.之间杆的拉力大小为2mgsinθ
C.球的加速度沿斜面向下,大小为2gsinθ
如图所示
B.C.三球的质量均为m,轻质弹簧一端固定在斜面顶端,另一端与A.球相连,A.
间固定一个轻杆,B.
间由一轻质细线连接。倾角为θ的光滑斜面固定在地面上,弹簧、轻杆与细线均平行于斜面,初始时系统处于静止状态。则在细线被烧断的瞬间,下列说法正确的是
A.B球的受力情况不变,加速度仍为零 B.A.B.两个小球的加速度均沿斜面向上,大小均为
gsin θ C.A.B.之间杆的拉力大小为
mgsin θ
C球的加速度沿斜面向下,大小为gsin θ
如图所示
B.C.三球的质量均为m,轻质弹簧一端固定在斜面顶端,另一端与A.球相连,A.,
间用一个轻杆连接,B.
间由一轻质细线连接.倾角为θ的光滑斜面固定在地面上,弹簧、轻杆与细线均平行于斜面,系统处于静止状态,在细线被烧断后瞬间,下列说法正确的是
A.B.球的受力情况未变,加速度为零 B.A.B.两个小球的加速度均沿斜面向上,大小均为1/2gsinθ C.A.,B.之间杆的拉力大小为2mgsinθ
C.球的加速度沿斜面向下,大小为2gsinθ
如图所示倾角为θ的固定光滑斜面底部有一垂直斜面的固定档板C.劲度系数为k1的轻弹簧两端分别与挡板C.
如图所示ABC三球的质量均为m轻质弹簧一端固定在斜面顶端另一端与A球相连AB间由一轻质细线连接BC间
A球的加速度沿斜面向上,大小为gsinθ
C球的受力情况未变,加速度为0
B、C两球的加速度均沿斜面向下,大小均为gsinθ
B、C之间杆的弹力大小为0
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假设你是红星中学高三学生李华请你根据以下四幅图的先后顺序给学校英语报投稿叙述你上周五早晨在上学路上经历的一次意外. 注意词数不少于60. 提示词后视镜rearviewmirror .
OvertheyearsIhavereceivedmanyChristmasgifts.HoweverthebestoneI'veeverreceivedwaspresentedbya41IneverknewhisnameandIonlyhad42withhimforlessthan60secondsbutthemomentchangedthe43IthinkaboutpeopleandChristmas. I44BlackFridaysales.It'softenlotsofpeople45theshopsmerelytopickupbargains.Theirintentionsarecompletelyunrelatedtothe46timeofyear. ItwasoneBlackFridaymorningseveralyearsago47mywifeandIwenttothelocaldepartmentstoretopurchaseachild's48forourson.Westoodwithaverylargecrowd49forthemanagetoblowthewhistle.Onhearingthe50peoplewereallscrambling争先恐后togetthebargains.I51myopportunityandliftedoneoftheboxescontainingbikes52Ifeltsomemildresistance.Ilooked53toseeoneofthelargestgentlemenI'deverseeninmylife.Frighteningwasnottheworldto54hispresence.Iunwillingly55theboxbuttomysurprisehegentlypusheditbackin56direction.Oureyesmadecontactandhegavemea57smilesayingMerryChristmas.MywifeandIwenttothe58andpaidforthebike.AllthewayhomeIwasthinkingthatthismomentwasmuchthebestChristmasgiftI'deverreceived.Asimple59ofkindnessfromastranger60allstereotypes成见andprejudicesImayhavehad.I'llneverforgetit. 41.A.friend B.colleague C.stranger D.brother 42.A.fun B.argument C.conversation D.contact 43.A.way B.habit C.attitude D.pattern 44.A.enjoy B.forget C.hate D.expect 45.A.breakinginto B.crowding C.gettinginto D.wandering 46.A.joyful B.discouraging C.annoying D.busy 47.A.since B.when C.before D.until 48.A.toy B.book C.box D.bike 49.A.preparing B.looking C.waiting D.crying 50.A.whistle B.bell C.screams D.cheers 51.A.missed B.saw C.offered D.quitted 52.A.Gradually B.Immediately C.Occasionally D.Suddenly 53.A.down B.up C.through D.forward 54.A.introduce B.state C.describe D.say 55.A.takeaway B.takedown C.putaway D.putdown 56.A.his B.its C.my D.another 57.A.friendly B.regretful C.frightening D.special 58.A.exit B.checkout C.store D.stand 59.A.act B.behavior C.word D.movement 60.A.deepened B.replaced C.cleaned D.removed
BlackFridayisthedayafterThanksgivingDayintheUSAfallingontheFridayafterthefourthThursdayinNovember. 36 ManypeoplehaveadayoffworkorchoosetotakeadayfromtheirannualleaveonBlackFriday.Somepeopleusethistomaketripstoseefamilymembersorfriendswholiveinotherareasortogoonvacation.ShoppingforChristmaspresentsispopularonBlackFriday.Manystoreshavespecialoffersandlowertheirpricesonsomegoodssuchastoys. Publiclife 37.ManypeopletakeadayoffonthedayafterThanksgivingDay.ManyorganizationsalsoclosefortheThanksgivingweekend. Publictransitsystemsmayrunontheirnormalscheduleormayhavechanges.SomestoresextendtheiropeninghoursonBlackFriday.38. Background BlackFridaythedayafterThanksgivingDayisoneofthebusiestshoppingdaysintheUSA.39.OnetheoryisthatthewheelsofvehiclesinheavytrafficonthedayafterThanksgivingDayleftmanyblackmarkingontheroadsurfaceleadingtothetermBlackFriday. TheothertheoryisthatthetermBlackFridaycomesfromanoldwayofrecordingbusinessaccounts.40.ManybusinessesparticularlysmallbusinessesstartedmakingprofitsbeforeChristmas.ManyhopedtostartshowingaprofitmarkedinblackinkonthedayafterThanksgivingDay. MorerecentlyBlackFridayhasbeenexportedtonationsoutsideofNorthAmericasuchastheUnitedKingdombymajoronlineretailerslikeAmazonorApple.In2011IBMreportedonlineBlackFridaysaleswereupby24.3%accordingtoastudythatincludes500retailers. A.People'sactivities. B.HistoryofBlackFriday. C.Losseswererecordedinredinkandprofitsinblackink. D.A.busyshoppingdayisaholidayinsomestates. E.Therecanalsobejamsonroadstopopularshoppingdestinations. F.TherearetwopopulartheoriesastowhyitiscalledBlackFriday. G.BlackFridayisnotafederalholidaybutapubliconeinsomestates.
已知水杨酸酯E为紫外吸收剂可用于配制防晒霜.E的一种合成路线如图 已知D的相对分子质量是130.请回答下列问题 1一元醇A中氧的质量分数约为21.6%.则A的分子式为结构分析显示A只有一个甲基A的名称为 2第④步的反应条件为写出E的结构简式 3B能与新制的CuOH2发生反应该反应的化学方程式为 4写出同时符合下列条件水杨酸的同分异构体的结构简式 a能与FeC13发生显色反应b能与银氨溶液反应c能发生水解反应 d核磁共振氢谱显示有四组峰.且峰面积比为1221
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甲醇乙二醇丙三醇中分别加入足量的金属钠产生等体积的氢气相同条件则上述三种醇的物质的量之比是
LakewayMiddleSchoolNowHasItsOwnSchoolStore! TheLion'sDen StopbytheLion'sDenbeforeorafterschoolorduringlunchtocheckoutthevariousgoodsavailableatournewschoolstore.Hereyoucanfindschoolsuppliesgymuniformsandgifts.Choir合唱团studentsmanagethestoreandarereadytoserveyou.Moneyraisedfromsaleswillhelppurchasenewmusiccostumesandsoundequipmentforthechoir. LocationRoom2258nexttothedininghall HoursMonday﹣Friday730﹣800A.M.1130A.M.﹣130P.M.and330﹣415P.M. EverythingyouneedforschoolisavailableattheLion'sDen.Comeintodaytoseeforyourself! UsedBookDonations Donationsofusedbooksarewelcomeandrewarded.Dropoffyourusedbookdonationsinthestore.ForeveryfivebooksdonatedreceiveaLionsRewardCoingoodfor25centsoffyournextpurchaseattheLion'sDen. SaveandWin Bringthefollowingcoupons优惠券inwhenyouvisittheLion'sDen.Youcansave20%offyourfirstpurchasereceiveafreepenorpencilandenteryournameandgradeinadrawingtowinaT﹣shirt.ScantheQRcodeandyoucangetmorediscountinformation. 56.TheLion'sDenraisesmoneyto. A.buybooks B.helpschoolchoir C.supportthepoor D.buildanewschool 57.Ifyoudonatefiveusedbooksyoucanget. A.aLionsRewardCoin B.20%off C.morediscountinformation D.afreepencilorpen 58.Yourpersonalinformationisneededto. A.getthemembership B.jointheschoolchoir C.winaT﹣shirt D.scantheQRcode 59.Wecanprobablyreadthispassagefrom. A.atextbook B.atravelguide C.asciencemagazine D.aschoolwebsite.
DangersfromOuterSpaceWhatisthegreatestthreattolifeonourplanet?Isitclimatechange?Shortagesoffoodorwater?Ormightanaltogetherbiggerdangercomefromsomewherefurtherawayspace?We'renottalkingaboutanattackbylittlegreenmenhere.Insteadhowaboutbeinghitbyalargefallingstarbeatbydeadlyuniversalraysorfriedbytheenergyofaneruptingstar?Itwouldn'tbethefirsttimethatourEarthhashadaroughrideoverthelast3.7billionyearswithsomedisastrousevents.Themostfamousmassextinction灭绝was66millionyearsagowhenit'swidelybelievedthatameteorite陨石killedoffthedinosaurs.A110﹣mile﹣widecraterinMexicowiththesamegeologicalagesupportsthistheory.Believeitornotthiswasn'ttheworstcatastropheinourplanet'shistory.Thatwaswhen96%oflifewaswipedoutattheendofthePermianperiod252millionyearago.Scientistsdon'tknowforsurewhythishappenedbutanypotentialexplanationscarrywiththemthepossibilitythatsimilareventscouldhappenagain.SomeexpertsbelievethatourSunhasatwinstarwhichistoofarawaytoobservedirectly.ThishugesleepingstarcouldtwistthepathsoforbitingicyrocksandcastthemtowardstherestoftheSolarSystem.Isthiswhathappened252millionyearsago?OristhereinsteadperhapsadistantninthplantinourSolarSystemwhichpullsinpassingcomets彗星andsendsthemdashingourway?TheSunthathasgivenusthewarmthisgraduallyturningintoadeadlyenemy.Likeallstarsitisslowingdyingburningthroughitsenergysupplies.Asitdoessoitexpandsandinabout2billionyearsitwillhavegrownsomuchthattheheatwillmakelifeonplanetEarthunbearable.Whileallthissoundsalittlehorribletakecomfortfromthefactthatthechanceofbeinghitbyahugeinterstellarprojectile星际碰撞物isunbelievablyslimandthat2billionyearsisaverylongtime.32.Whendiddinosaursdieoutaccordingtothepassage?A.3.7billionyearsago.B.252millionyearsago.C.66millionyearsago.D.2billionyearsago.33Whywas96%oflifedestroyedattheendofthePermianperiod?A.Thecauseisstillunknown.B.Ahugefallingstarhittheearth.C.AtwinstarcasticyrockstowardstheSolarSystem.D.Aninthplanetpulledinpassingcomets.34.Whatcanwelearnfromthepassage?A.Allstarswilleventuallyrunofenergy.B.Ourplanetwillbeattackedbylittlegreenmen.C.Wewillbefriedbytheenergyofaneruptingstar.D.Ahugesleepingstarwillhittheearthinmillionsofyears.35.Whatistheauthor'sattitudetowardthedangersfromouterspace?A.Frightened.B.Relieved.C.Worried.D.Doubtful.
ACanineReadingBuddy Dogsandpeoplehavedevelopedaspecialbondovertime.Recentlyhoweversomedogshavetakenadifferentroleinpeople'slives﹣therapydogs. 1Sometherapydogsvisitpatientsinhospitalsornursinghomeswhileothersvisitchildreninschoolsandlibraries.Theyaretheretohelpchildrenbecomebetterreaders. Readingprogramsthatusetherapydogshavebeeninexistenceformorethantenyears.Alltherapydogsofthisprogramareregisteredwithanorganizationthatteststhedogstomakesuretheyhavetherightpersonalityforthejob. 2Boththedogsandthehandlersarevolunteerswiththereadingprogram. Atthestartofareadingtherapysessionachildandadogareintroduced.Thepairisallowedtosettledowninaquietcornertogether.3Anadulthandlerstaysnearbybutgenerallyletsthedogperformitsjobwithoutinterfering干涉.Sometimesahandlermayaskaquestionthatencouragesthechildtoworkwiththedogtohelpthechildfeelmorecomfortable. Noteverychildwillbeabletobepartofareadingtherapyprogramthatusesdogs.Afewchildrenmightbeallergictodogsorafraidofthemsomechildrenmighthaveculturaltraditionsthatpreventthemfromtouchingadog.4 Readingtherapyprogramsinspirelearningandchange.5Theyspendtimewithhumanfriends.Fordogsthatlovehumancompanionshiopandaquietplacetorestbeingpartofareadingtherapyprogramcanbeagreatwaytospendafewhourseachday.Thereadersbenefittoogainingconfidenceandlearningthatreadingaloudcanbearelaxingexperience. A.Howdothetherapydogsbenefitfromit? B.Buttherapyanimalsalsoserveinmanyotherareas. C.Asthechildreadsthedogusuallyliesquietlyandlistens. D.Whenreadingtoananimalsomechildrenmaybecomerelaxed. E.Inthesecircumstancesotheranimalsareavailablesuchascatsandparrots. F.Atherapydogismoreofacompanionandistrainedtohelppeopleindifferentways. G.Adog'shandleralsotakesaclassandmustpassatesttoworkinthetherapyprogram.
lg2+lg5==.
若关于x的不等式ax2-6x+a2<0的解集是1m则m等于.
●UndergroundCityMontrealCanada Takeoneofthe120entrancesintothelargestman﹣madeundergroundnetworkintheworld. Montreal'sUndergroundCitywasfirstbuiltin1962.About500000peopleadayuseits32kilometersofshoppingmallsapartmentbuildingshotelsbanksofficesmuseumsanduniversitiestherearealsotwotrainstationsandabusterminal终点站. ●MammothCaveNationalParkKentuckyAmerica PlacenamessuchasGrandAvenueandFrozenNiagaragiveanideaofwhat'sintheworld'slongestundergroundcavesystem.Theoldestpartwasformed10millionyearsago9.5millionyearsbeforemanmadeanappearance. ●Hannan'sNorthMineKalgoorlieAustralia Godown30.5metersinacageelevatortotunnelsdugduringAustralia's19th﹣centurygoldrush.Tryyourhandatpanningforgold淘金.Kalgoorliestillproduces10percentoftheworld'sgold. ●WieliczkaSaltMineKrakowPoland Itallstartedwhensaltwasjustliketoday'soil.Ninecenturiesofmininghasproducedmilesofundergroudpassagesandhugecavestoadepthof134meters.MorethanonemillionpeopleayearvisittheUNESCO﹣listedsitewhichincludeslakesandstatuesmadefromsalttheworld'slargestminingmuseumandconcerthalls. ●BerlinNuclearBunker地堡Germany Takeafewminutestoadjusttothedim昏暗的lightofthis1971radiation﹣proofColdWarbunker.Feelthecoldenteryourbonesinthedeathlysilence.Thenarrowbedsfor3562peopletakeupmostofthespace.Thebunkercouldoperatefor14daysafteranuclearattack.It'safrighteningexperience. 21.Whatdotheabovefiveattractionhaveincommon? A.Theyareallman﹣made.B.Theyalllieunderground. C.Theyareallradiation﹣proof.D.Theyalldatebacktothe19thcentury. 22.InWieliczkaSaltMinevisitorscan. A.makesaltstatuesB.enjoythemountainscenery C.learnaboutsaltmininghistoryD.experienceminingsaltthemselves 23.Wecaninferfromthepassagethat. A.Hannan'sNorthMineisoutofoperation B.BerlinNuclearBunkeriswell﹣equippednow C.MammothCaveNationalParkhastheworld'soldestcavesystem D.UndergroundCitywasbuilttomakecitizens'lifemoreconvenient 24.Wecanmostprobablyreadthepassageina. A.newsreportB.historymagazineC.travelguideD.researchpaper.
根据实验操作与现象所得结论正确的是
已知函数fx=xex-x-ax2. Ⅰ若曲线y=fx在点1f1处的切线与直线y=-x+1平行求实数a的值 Ⅱ当x≥0时fx≥0.求实数a的取值范围.
如图示为一种天然产物具有一定的除草功效下列有关该化合物的说法错误的是
图示为甲乙两物体的位移随时间变化关系的x﹣t图象下列说法中正确的是
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处错误每句中最多有两处.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字符号∧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. LookingbacktotheNationalEnglishSpeakingCompetitionItakepartinseveraldaysagoIhavealottosharetoyou. FirstlyIfeelrealdelightedthatI'vewonthefirstprizeinthecompetitionwhichmakesmetounderstandthetruemeaningoftheproverbNopainsnogains.BesidesI'veestablishedthefriendshipwithstudentsfromalloverourcountryfromwhichI'velearnedalot.Moreimportantlyparticipateinthiscompetitionhasenabledmetoovercomemyfearofspeakinginpublicthusdevelopingmyself﹣confidence.AdditionallyIowemuchthankstomyteachersandjudges.WithouthishelpIcouldn'thavedonesuchexcellentjob. TosumupIwillalwaystreasurethismeaningfulandmemorableexperiences.
Imaginelookingataviewofmountaintopsandwonderingaboutthenameofeachpeak.Suddenlyaboveeachmountaintopanameappearsonthesky.Thewordsarenotwritteninsmokebyskywritingplanes.Thewordsareactuallynotintheskyatall.Theycomefromtinycomputersincontactlenses隐形眼镜. Computershavebecomesmallerandsmalleroverthedecades.Thefirstcomputersfilledhouses.Transistors晶体管andthenchipsallowedcomputerstobecomesmallenoughtofitonadesktopthenalaptopandfinallyaphone.Whenexperimentingwithfurtherreductionsinsizedevelopersoftenhavetodealwiththelimitsofhumaneyesightwhichcontrolhowsmallthecomputerscanbeandstillpresentvisibleinformation. Onenewsolutionemploysmicroprojectors微型投影机tocreateareadabledisplay显示fortinycomputers.Thesemachinesprojectcomputerinformationontoanysurface.Thoughanimpressivebreakthroughtherearepotentialproblems.Suchpublicdisplayscanleadtoprivacyconcernsmostpeopledonotwanttheirinformationdisplayedonawallforeveryonetosee.Besidestheseprojectorsareextremelyexpensiveandtheirscreensgiveusersheadaches. BabakParvizaresearcherattheUniversityofWashingtoncreatedanothersolutioninventingascreenvisibleonlytoapersonwearingacontactlens.Parvizcreatedacomputerinacontactlensthatusesthewearer'sfieldofvisionasthedisplay.TocreatethedisplayParviztookordinarysoftcontactlenseswithawirelesslycontrolledsystem.AtsomepointParvizsaysitwillbepossibletoconnectthelenstoaremotepersonalcomputerdevicesuchasacellphoneoralaptop.Bylookinginacertaindirectionthewearersendsthecomputervisualinformationaboutwhatheorshesees.Thedevicethenusesthisinformationtopointoutthenamesofpeaks. Thesecontactlensesareinsertedandremovedinmuchthesamewayasordinarycontactlenses.Inadditionthecomputersinthelenseswon'tblockthewearer'ssightatall.AlthoughnowthecomputersarenotonlensestreatingeyesightproblemsParvizhopesthatsomedaythetechnologywillprogresstothatlevel. 63.Thecontactlensesinthetextcan. A.treateyesightproblems B.offerbeautifulviewsofnature C.projectinformationonwallsurface D.showinformationaboutwhatwearerssee 64.AccordingtoParagraph3themicroprojectors. A.putpeople'sprivacyatrisk B.savecomputerinformation C.causeseriousillnesses D.supportusers'needs 65.Accordingtothepassagethesecontactlensescontributeto. A.savingusers'expenses B.reducingcomputers'size C.limitingthefieldofvision D.guardingremotecomputers 66.Whatmightbethebesttitleforthepassage? A.TinyComputersAmazingSights B.SmallerLensesCloserViews C.ProgresstowardsClearness D.RoadtotheSmallWorld.
美国某中学举办英语暑假训练营开设以下课程cookingswimminggivingfirst﹣aidplayingfootball/basketball.假定你是李华请你写封申请信报名参加其中一门课程的学习.内容包括1.你感兴趣的一门课程2.为什么想学这门课程3.你期望从中学到什么.注意1.词数100左右2.可以适当增加细节以使行文连贯.DearSir/MadamYoursLiHua.
ThereareplentyofthingsyoucanfeelpositiveknowingaboutGarfield﹣thecatwholoveslasagnahatesMondaysandadoresateddybearnamedPooky.ButlastweekwithoutwarningthereroseastrangeandsuddendebatearoundaquestionaboutthefamouscatthatevencreatorJimDavisneededtoweighinonIsGarfieldaboyagirlornogender性别atall? TheargumentappearstohavebegunwhenwriterVirgilTexascameacrossa2014MentalFlossinterviewwithDaviswherehedescribedhistabbycreationGarfieldasnotreallymaleorfemaleoranyparticularraceornationalityyoungorold. Inresponsetothequote引用VirgilwroteonTwitterFACTGarfieldhasnogender.This.Is.Definite.SosurewasheofGarfield‘struegenderstatusthatVirgileventookituponhimselftoupdatetheGarfieldcharacterWikipediapagewiththeinformation. ButitwasquicklyclearthatnoteveryoneagreedwithVirgil‘seditsandthusbeganawarovertheWikipediaentryedits.SomementionedthatGarfieldismale.Otherswrotethatitshouldn'tmatteratallwhetherGarfieldismaleorfemale.WashingtonPostreportedthatthebattletookplaceover60hoursandeventuallyendedwhenWikipediashutthingsdownbylockingthepage. ItwasastatementthatsoonappearedtohavebeenmadeinhurryasJimDavisindeedsoonjoinedthedebateshuttingeverythingdowninonelinetoWashingtonPostGarfieldismale.The71﹣year﹣oldcartoonistalsopointedoutthatGarfieldhasagirlfriendArleneandclaimedthathis2014quoteshadbeentakenoutofcontext.I'vealwayssaidthatIwantedtoworkwithanimalsbecausethey'renotregardedasbeinganyparticulargenderraceageorethnicityhesaid.Inthatsensethehumorcouldbeenjoyedbyabroadergroup. 24.Whatdoesthepassagemainlydiscuss? A.AnargumentaboutthegenderofGarfield. B.TheinterviewbetweenJimDavisandVirgilTexas. C.AnupdateofWikipediaentryeditsaboutGarfield. D.ThepopularityofthefamouscartooncharacterGarfield. 25.Whatdoestheunderlinedphraseweighinonprobablymean? A.Agreewith. B.Joinin. C.Putforward. D.Careabout. 26.ThedebateonlineuponthegenderofGarfieldwasendedupby. A.writerVirgilTexas B.Wikipedia C.WashingtonPost D.creatorJimDavis 27.Whatcanbeinferredfromthelastparagraph? A.JimDavis'2014quoteshadbeencutout. B.Garfieldbecomesmorefamousthanbefore. C.WashingtonPostshuteverythingdowninonelineaboutGarfield. D.ThecreationofGarfieldisaimedatentertainmentratherthananythingelse.
WhenothersgetoffthetraintofinallygohomeLeonieMullerslaysbehind.That'sbecausesheisalreadyhomeThetrainisherapartmentandshesaysshelikesitthatway.TheGermancollegestudentgaveupherapartmentinspring.ItallstartedwithanargumentIhadwithmylandlordMullertoldTheWashingtonPostviae﹣mail.IimmediatelydecidedIwanttolivethereanymoreandthenIrealizedActuallyIdidn'twanttoliveanywhereanymore. Insteadsheboughtasubscription会员费thatallowshertoboardeverytraininthecountryforfree.NowMullerwashesherhairinthetrainbathroomandwriteshercollegepaperswhiletravelingataspeedofupto190mph.Shesaysthatsheenjoysthefreedomsinceshegaveupherapartment.Ireallyfeelathomeontrains.It'slikebeingonvacationallthetimeMullersaid. IwanttoinspirepeopletoquestiontheirhabitsandthethingstheyconsidertobenormalMullertoldThePost.Therearealwaysmoreopportunitiesthanonethinksthereare.Thenextadventureiswaitingjustaroundthecomer﹣providedthatyouwanttofindit. Mullerfrequentlytravelslateatnightalthoughshetriestosleepattheapartmentsofrelativesorfriends.Oftensheisaccommodatedbyherboyfriendhermotherorgrandmother.Normallywewouldhavetohavealong﹣distancerelationshipbutlivingonatrainenablesmetoseehimallthetimeMullertoldGermanTVstationSWRregardingherboyfriend.Mostofrayfriendsreallyliketheideaalthoughsomeconsiderittobequiteadventurous.Othershoweverhavereactedmorenegatively.TheyfeeloffendedbythefactthatIquestiontheordinarywayoflifeandliving. Theonlyproblem?Possessingaheadsetthatreducesmostsurroundingnoisesisimportantshesaid. 28.WhatdoweknowaboutthedirectreasonforMullerschoicetoliveontrains? A.Shehadanargumentwithherlandlord. B.Shewantedtovisitmorepeopleontheway. C.Shehadtofinishhergraduatepaperonthetopic. D.Sheplannedtoactagainsttradition. 29.AccordingtoMullerwhichisoneoftheadvantagesoflivingontrains? A.Shecanhavemoreholidays. B.Shecanescapefromcollegelife. C.Shecanpossessaheadset. D.Shecanseeherboyfriendmoreoften. 30.WhatdoesMullerwanttoexpressinParagraph3? A.Thereareopportunitieseverywhereinlife. B.Thenextadventureiscomingsoon. C.Peopleneedtomakechangesintheirlife. D.Peopleneedtofollowinherfootstepstoliveontrains. 31.WhatdoestheunderlinedworditinParagraph4referto? A.Theordinarywayoflifeandliving. B.Thethoughtoflivingonatrain. C.GermanTVstationSWR. D.Along﹣distancerelationship.
有各不相同的5红球3黄球2白球事件A从红球和黄球中各选1球事件B从所有球中选取2球则事件A发生是事件B发生的
Nowadaysmoreandpeoplehavechancestotravelstudyworkorevenliveabroad.Itisnecessaryforyoutokeepinmindthesegeneral61ruleforpolitebehavior. Ifyou62invitetoanAmericanfriend'shomefordinnerfirstofallarriveapproximatelyontimebutnotearly.Americansexpectpromptness准时. Whenyou'reinvitedtosomeone'shomeforameal63ispolitetobringasmallgift.Flowersorcandiesarealwaysappropriate.Ifyouhaveanattractiveitem64makeinyournativecountryyourhostorhostesswouldcertainlyenjoyreceivingthatasagift. Wearingproperclothesandabeautifulsmileissimplynotenough.Tablemannersarealsoofgreat65important.Donotopenyourmouthtotalk66youhaveswallowedyourfood.Alsochewfoodwithyourmouth67close.Whenyouwanttogetthefoodthatisatadistancedonotstretchyourhandstoreach68it.Insteadaskforthefoodtobepassedtoyou. Don'tleave69immediateafterdinnerbutdon'toverstayyourwelcomeeither.Whenyourfriendsseemtobegettingtiredandrunningoutofconversationtaketheirbehaviorasasignaltoleave.Thenextdaycallorwrite70thank﹣younotetosayhowmuchyouenjoyedtheevening.
有机物有多种同分异构体其中属于酯类且氯原子直接连在苯环上的同分异构体有多少种不考虑立体异构
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