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如图所示，空间有一正三棱锥OABC，点A′、B′、C′分别是三条棱的中点．现在顶点O处固定一正的点电荷，则下列说法中正确的是（ ）
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高三下学期物理《》真题及答案
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在正三棱锥V.﹣ABC内有一半球其底面与正三棱锥的底面重合且与正正三棱锥的三个侧面都相切若半球的半径
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Ifyoufeelstressedbyresponsibilitiesatworkyoushouldtakeastepbackandidentify识别thoseof61greatandlessimportance.Thenhandlethemostimportanttasksfirstsoyou'llfeelarealsenseof62achieve.Leavingthelessimportantthingsuntiltomorrow63beoftenacceptable.Mostofusaremorefocused64ourtasksinthemorningthanwearelaterintheday.Sogetanearlystartandtrytobeasproductive65possiblebeforelunch.Thiswillgiveyoutheconfidenceyouneedtogetyouthroughtheafternoonandgohomefeelingaccomplished.Recent66studyshowthatwearefarmoreproductiveatworkifwetakeshortbreaks67regular.Giveyourbodyandbrainarestbysteppingoutsidefor68whileexercisingordoingsomethingyouenjoy.Ifyoufindsomethingyoulovedoingoutsideoftheofficeyou'llbelesslikely69bringyourworkhome.Itcouldbeanything﹣gardeningcookingmusicsports﹣butwhateveritis70makesureit'sarelieffromdailystressratherthananotherthingtoworryabout.
在一次连环交通事故中只有一个人需要负主要责任但在警察询问时甲说“主要责任在乙”乙说“丙应负主要责任”丙说“甲说的对”丁说“反正我没有责任”四人中只有一个人说的是真话则该事故中需要负主要责任的人是
Agardenthat'sjustrightforyouHaveyouevervisitedagardenthatseemedjustrightforyouwheretheatmosphereofthegardenappearedtototalmorethanthesum总和ofitsparts?36.Butitdoesn'thappenbyaccident.Itstartswithlookinginsideyourselfandunderstandingwhoyouarewithrespecttothenaturalworldandhowyouapproachthegardeningprocess.●37Somepeoplemaythinkthatagardenisnomorethanplantsflowerspatternsandmassesofcolor.Othersareconcernedaboutusinggardeningmethodsthatrequirelesswaterandfewerfertilizers肥料.38.Howeverthereareanumberofotherreasonsthatmightexplainwhyyouwanttogarden.Oneofthemcomesfromourearliestyears.●Recall回忆yourchildhoodmemoriesOurmodelofwhatagardenshouldbeoftengoesbacktochildhood.Grandma'srosegardenandDad'svegetablegardenmightbegoodorbadbutthat'snotwhat'simportant.39﹣﹣howbeinginthosegardensmadeusfeel.Ifyou'dliketobuildapowerfulbondwithyourgardenstartbytakingsometimetorecallthegardensofyouryouth.40thengooutsideandworkoutaplantotranslateyourchildhoodmemoriesintoyourgrown﹣upgarden.Havefun.A.KnowwhyyougardenB.FindagoodplaceforyourowngardenC.It'sourexperienceofthegardenthatmattersD.It'sdelightfultoseesomanybeautifulflowersE.StillothersmaysimplyenjoybeingoutdoorsandclosetoplantsF.YoucanproducethatkindofmagicalqualityinyourowngardentooG.Foreachofthosegardenswriterdownthestrongestmemoryyouhave.
假定你是李华你校摄影俱乐部photographyclub将举办国际中学摄影展.请给你的英国朋友Peter写封信.请他提供作品.信的内容包括 1.主题环境保护 2.展览时间 3.投稿邮箱intlphotoshow@gmschool.com. 注意 1.词数100左右 2.可以适当增加细节以使行文连贯.
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