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在半径为6cm的圆中，圆心角为120°的扇形的面积是 cm2．
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将一个圆心角为120°半径为6cm的扇形围成一个圆锥的侧面则所得圆锥的高为cm.
已知扇形的半径为6cm圆心角为150°则此扇形的弧长是5πcm扇形的面积是15πcm2结果保留π.
已知扇形的圆心角为120°半径为6cm的圆则扇形的弧长为
3cm
3πcm
4cm
4πcm
用半径为6cm圆心角为120°的扇形围成的圆锥的底面圆半径为cm.
如图有一圆心角为120o半径长为6cm的扇形若将O
OB重合后围成一圆锥侧面，那么圆锥的半径是（ ）
A. 1cm
2cm
3cm
4cm
如图有一圆心角为120°半径长为6cm的扇形OAB若将OAOB重合后围成一圆锥侧面那么圆锥的高是cm
已知扇形的半径为6cm圆心角的度数为120°则此扇形的弧长为cm.
一个扇形所在圆的半径为3cm扇形的圆心角为120°则扇形的面积是cm2.结果保留
用一个圆心角为120°半径为6cm的扇形作一个圆锥的侧面则这个圆锥的底面圆的半径为.
已知扇形的圆心角为120°半径为6cm用这个扇形围成一个圆锥的侧面则此圆锥的底面半径为cm.
如图已知扇形AOB的圆心角为120°半径为6cm求扇形的弧长及所含弓形的面积.例4
已知扇形的圆心角为60º半径为6cm则扇形的弧长为cm.
圆心角为120°半径为6cm的扇形面积为__________cm2.
用半径为6cm圆心角为120°的扇形围成一个圆锥则圆锥的底面圆半径为cm．
在半径为1cm的圆中圆心角为120°的扇形的弧长是cm;
已知扇形的圆心角为120º半径为6cm则扇形的弧长为cm.
一圆锥的侧面展开后是扇形该扇形的圆心角为120°半径为6cm则此圆锥的表面积为_______cm2.
圆心角为120°半径为6cm的扇形的弧长是
在半径为6cm的圆中120°的圆心角所对的弧长为cm.
如图有一圆心角为120°半径长为6cm的扇形OAB若将OAOB重合后围成一圆锥侧面那么圆锥的高是cm
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Everybodyhatesrats.Butintheearthquakecapitalsoftheworld﹣JapanLosAngelesandTurkeyratswillsoonbeman'snewbestfriends. Whathappensafteranearthquake?Wesendinrescuedogs.Why?Becausetheycansmellpeople.Dogssavelives.Theyhelprescuerstofindlivingpeople.Butdogsarebigandtheycan'tgetintosmallspaces.Sonowanewresearchprojectisusingasmalleranimaltosavelives:therat. Howdoesitwork?Firsttheratistrainedtosmellpeople.Whenthishappenstherat'sbraingivesasignal信号.Thisissenttoasmallradioonitsbackandthentherescuersfollowthe radiosignals.Whentherat'sbrainactivityjumpstherescuersknowthatsomeoneisalive.Therathassmelledthatperson. Althoughtherearealreadyrobotswhichcandothisjobratsarebetter.ChristianLinsteratCornellUniversity﹣NewYorksaysRobots'nosesdon'tworkwellwhenthereareothersmells around.Ratsaregoodatthat.Ratscanalsoseeinthedark.Theyarecheaperandquickertotrainthandogsandunlikerobotstheydon'tneedelectricity! TheratprojectisnotfinishedyetbutJulieRyanofInternationalRescueCorpsinScotlandsaysItwouldbefantastic.Aratcouldgetintospaceswecouldn'tgettoandaratwouldgetoutifitwasn'tsafe.Perhapsforthefirsttimeinhistorypeoplewillbehappytoseearatinabuilding butonlyafteranearthquakeofcourse. 1.Intheworldearthquakecapitalsthereasonwhywillcatsbecomeman'sbestfriendsisthat. A.theycantaketheplaceofman'srescuejobs B.theycanfindthepositionofpeoplealivewhoaretrappedinbuildings C.theycanserveasfoodforpeoplealivewhoaretrappedinbuildings D.theycangetintosmallspaces 2.Fromthethirdparagraphweknowtherescuerscanjudgeapersonisaliveby. A.thenoisemadebytherat B.therat'sunusualbehavior C.thesignalsentbytheradioontherat'sback D.thesmellgivenoffbytheperson 3.Theunderlinedwordrescuersisclosestinmeaningto. A.doctors B.assistants C.savers D.workers 4.Ratshaveallthefollowingadvantagesexceptthat. A.theyaremorefantasticthanotheranimals B.theyarelessexpensivetotrainthandogs C.theydon'tneedelectricity D.theyaresmallandcangetintosmallplaces 5.Wecanlearnfromthepassagethat. A.ratshavetakentheplaceofdogsinsearchingforpeopleatpresent B.theratprojecthasbeencompleted C.peoplearenowhappytoseearatinabuilding D.peoplestillusedogsandrobotsinperformingrescuesnow
Althoughcarnival狂欢节iscelebratedincitiesandvillagesthroughoutBrazilandotherCatholictiān zhǔ jiāo 的countriesRiodeJaneiro里约热内卢haslongbeenregardedasthecarnivalcapitaloftheworld.TheRioCarnivalisoneofthebiggestcarnivalsaroundtheworld.AlmosteveryonehasheardofRioCarnival.Everyyeararound500000foreignvisitorscometoBraziltospendtheRioCarnival. WhentheRioCarnivalcomespeopledancesingandhaveparties.TherearemanypartiesthattakeplacebeforeduringandafterCarnival.Peoplehavepartiesallnightandallday.CarnivalisveryimportanttotheBrazilians.TheRioCarnivalnotonlyprovidesentertainmentformanypeoplearoundtheworldbutalsogivesachancetolearnaboutthecultureofBrazil. TheRioCarnivalistheresultofseveralmonthsofpreparation.Peopleusuallycan'twaittoexpectthestartofeachyear'sRioCarnival.ItbeginswiththecrowningoftheFatKingwhoispresentedwithagiantsilverandgoldkeybythecity'smayor.Thenyoucanfindgroupsofpeopleparade游行alongthestreets.Duringtheseven﹣daycarnivalthecityisfullofmusicandalmostallofthemusicplayedduringRioCarnivalissamba.Sambaisakindofmusicwhichisfullofpassionandenergy.Itcanmakepeopleexcited. 1.AccordingtothepassagewhathasRiodeJaneirobeenconsidered? RiodeJaneirohasbeenconsidered. 2.AccordingtothepassagehowlongdoestheRioCarnivallasteveryyear? EveryyeartheRioCarnivallastsfor. 3.WhatisthemusicthatismostplayedinRioCarnival? MostofthemusicthatisplayedinRioCarnivalis. 4.InRioCarnivalhowdopeoplealwayshavefun? InRioCarnivalpeoplealwayshavefunby. 5.WhydoBraziliansandforeignersthinktheRioCarnivalisveryimportant? BecausebutalsogivesachancetoknowthecultureofBrazil.
在北极的一个山脉中原始的狼已经形成在体格和生活习性上不同的变种其中一种狼的体重较轻四肢发达而灵活以猎鹿为主另一种狼的体重较重足短而力强常常攻击羊群．下列叙述错误的是
基因组编辑技术是研究基因生物功能的重要手段如图是对某生物B基因进行定点编辑的过程该过程中用sgRNA可指引核酸内切酶Cas9结合到特定的切割位点相关说法不正确的是
﹣﹣isitfromXi'antoShanghai?﹣﹣Lessthanthreehoursbyair.A.Howmany B.Howfar C.Howsoon D.Howlong
阅读下面一篇短文判断下列句子是否符合短文内容符合的用A表示不符合的用B表示. KobeBryantisthesonofformerNBAplayerJoeBryantandwasbornin1978inPhiladelphia.EventhoughhisgradesweregoodtheyoungerBryantchosetojointheNBAafterhighschool. DelHarristhecoachofLakersbroughtKobeintohisfirstNBAgamewhenhewasonly18yearsold.OverthenextthreeseasonsBryantshowedplentyofability. Thefollowingthreeyears﹣20002001and2002werethegoldenyearsfortheLakers.KobeBryantandShaquilleO'NealformedadreampartnershipandtheLakerswonthreestraightchampionships.KobealsowonagoldmedalattheOlympicswithTeamUSAin2008. Howeverin2015everybodyknewthattheLakersera时代cametoanend.Kobehadledhisteamtoamazingheightsbuthistimewascomingtoanend.OnNovember292015Kobeannouncedthathewouldretireattheendoftheseason. 1.BryantchosetojointheNBAbecauseofhisbadgrades. 2.AsabasketballplayerKobeneverlostagame. 3.Kobe'steamwonagoldmedalattheOlympicsinBeijing. 4.Kobe'sfatherusedtobeabasketballplayer. 5.ThepassagetellsusKobe'slifetime.
少开车对环境有好处. Todrivelessistheenvironment.
A:Howwasyourweekend? B:1.Ireallyenjoyedit. A:Ohdidyougoanywhere? B:YesIwenttoXi'anArtMuseumwithmyfriends. A:2? B:Becausewearepreparingforourschoolartfestivalandwewanttolearnsomethingfromit. A:Yourschoolartfestival?3? B:It'sanartfestivalforstudentstoshowtheircreativeworks. A:That'sinteresting.4? B:Welearnedhowtolayouttheexhibitionhall展厅. A:Soundsmeaningful.5. B:Thankyou.I'msurewewillbesuccessful. 1. 2. 3. 4. 5.
如图为某二倍体雌性生物细胞不同分裂时期的模式图ⅠⅡ表示染色体片段．请分析作答 1甲细胞处于分裂中期该细胞中有同源染色体对姐妹染色单体条． 2若甲乙两细胞来源于同一个卵原细胞细胞乙是卵细胞则甲细胞的名称为． 3甲细胞时期不能进行转录的原因是但核糖体仍能进行翻译的原因是． 4细胞乙形成过程中发生的基因重组包括有．
一人体精原细胞2N＝46所有的染色体上的DNA双链均用15N标记置于14N条件下培养完成一次有丝分裂和一次减数分裂仅就被标记的染色体数目而言最终最少可能产生多少种子细胞最多可能产生多少种子细胞
已知SARS是由一种RNA病毒感染所引起的疾病．SARS病毒表面的S蛋白是主要的病毒抗原在SARS病人康复后的血清中有抗S蛋白的特异性抗体．某研究小组为了研制预防SARS病毒的疫苗开展了前期研究工作．其简要的操作流程如下 1实验步骤①所代表的反应过程是． 2步骤②构建重组表达载体A和重组表达载体B必须使用限制性内切酶和DNA连接酶后者的作用是将限制性内切酶切割的和连接起来． 3如果省略步骤②而将大量扩增的S基因直接导入大肠杆菌一般情况下不能得到表达的S蛋白其原因是S基因在大肠杆菌中不能也不能． 4为了检验步骤④所表达的S蛋白是否与病毒S蛋白有相同的免疫反应特性可用大肠杆菌中表达的S蛋白与进行抗原﹣﹣抗体特异性反应实验从而得出结论． 5步骤④和⑥的结果相比原核细胞表达的S蛋白与真核细胞表达的S蛋白的氨基酸序列相同根本原因是．
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