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绿茶是安徽的特产，种类很多，绿茶制作过程如下，其中包含化学变化的是（ ） A．采摘嫩叶 B．炒熟氧化 C．揉捻成型 D．干燥装袋
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绿茶的制作工艺分为和是形成绿茶品质的关键
绿茶是安徽的特产种类很多绿茶制作过程如下其中包含化学变化的是
采摘嫩叶
炒熟氧化
揉捻成型
干燥装袋
绿茶的制作工艺分为________________和________________是形成绿茶品质的
绿茶是我国产茶量最多的种类绿茶的基本特征是
恩施玉露茶产于属于茶
湖南省，炒青绿茶
安徽省，烘青绿茶
贵州省，蒸青绿茶
陕西省，烘青绿茶
湖北省，蒸青绿茶
以西湖龙井洞庭碧螺春为代表的绿茶是中国产量最多的茶叶除了绿茶中国还有红茶乌龙茶黑茶等种类的茶叶这些茶
制作工艺
颜色
产地
口味
绿茶的制作工艺
高桥银峰茶产于属于茶
浙江省，花茶
安徽省，绿茶
福建省，白茶
湖南省，绿茶
江西省，红茶
茶是我国的特产种类很多其中绿茶是将新鲜的茶叶炒熬破坏其中酵素再经搓揉烘焙而成茶叶的化学成分主要是茶碱
太平猴魁茶产于属于茶
浙江省，花茶
安徽省，绿茶
福建省，白茶
湖南省，绿茶
江西省，红茶
绿茶是安徽的特产种类很多绿茶是将新鲜的茶叶炒熬破坏其中酵素再经搓揉烘焙而成茶叶的化学成分主要是茶碱C
茶碱由四种元素组成
一个茶碱分子中含24个原子
茶叶是混合物
茶碱中氧元素的质量分数最大
特种绿茶作为绿茶一类其制作工艺也分为三步
萎凋
杀青
揉捻
干燥
绿茶制作过程中形成绿茶品质最关键工序是
简述绿茶的制作过程为什么要进行杀青杀青有几种方式
下列有关绿茶的表述不正确的是
绿茶是最古老的茶叶品种
是发酵的茶叶
初制时采用高温杀青
制作过程中不保持鲜叶原有的嫩绿
中国绿茶产量大，品种多
绿茶是制作时不经的具有特征的茶类经而成绿茶根据杀青方式和最终干燥 方式的不同可分为四类 ______
杀青是黄茶品质形成的基础但其杀青过程中的温度要求是要
比绿茶的略低
与绿茶的相当
比绿茶的略高
比绿茶的高很多
绿茶按制作工艺可分为炒青烘青蒸青四大种类
杀青
煮青
晒青
烘烤
黄茶分为黄芽茶黄小芽茶和黄大芽茶黄茶属于部分发酵类制作方法与绿茶相似具有绿茶的特点 黄茶与绿茶加工相
发酵
闷黄
杀青
干燥
茶是我国的特产种类很多其中绿茶是将新鲜的茶叶炒熬破坏其中酵素再经搓揉烘焙而成茶叶的化学成分主要是茶碱
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某品牌矿泉水其外包装上部分文字说明如图所示请回答下列问题． 1用结构示意图表示氯化钾中阴离子的核外电子排布 2标出偏硅酸H2SiO3中硅元素的化合价 3已知偏硅酸的化学式为H2SiO3则偏硅酸钙的化学式为 425℃时该矿泉水呈．填“酸性”“中性”或“碱性”
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正是为了人民的利益一些政府官员抵制金钱和权力的__将经济改革进行到底.It.
如图一个重力为10N的物块以20m/s的速度冲上了高为5m长为10m的光滑斜面达到斜面顶端时物块的速度恰好减小为0．对此过程以下分析正确的是
Talkingtohuman﹣likedevicescanbegreatfun﹣justaskSiritotellyouajoke.Butitmuyalsoleadtoproblems. ArecentstudybyscientistsfromtheUniversityofKansasintheUSfoundthathuman﹣likedeviceskeeppeoplefromseekingoutnormalhumaninteractionwhentheyfeellonely. Duringaseriesofexperimentspanicipantswereaskedtowriteaboutatimewhentheyfeltlonely.Theyalsotookpartinanonlinegameofcatchagainstacomputerprogramthatwasdesignedtothrowthehalltootherplayersmoreoftenbutparticipantsbelievedtheywereplayingwithrealpeopleonline. Participantswerethenintroducedtohuman﹣likeproductsincludingavacuumcleaner真空吸尘器designedtoappearasifitweresmiling.Theywerealsoaskedtothinkabouttheirphoneinhuman﹣liketermsconsideringquestionslikehowmuchdoesithelpyou Theresultsshowedthattheparticipantswerehappywiththecomforttheygotfromthemachinesanddidn'tneedtoseekoutnormalhumaninteraction. Generallywhenpeoplefeelsociallyexcludedtheyseekoutotherwaystoreduce thefeelingofloneliness.NormalwaysincludeincreasingtheirnumberofsocialmediafriendsorengaginginbehaviorstoseekoutinteractionwithotherpeopleaccordingtoJennyOlsonassistantprofessorofmarketingatKU. Butitwasn'tallbadnewsastheteamfoundthattherewerelimitstohowfarthiseffectwouldextend. Assoonaswetellpeopleweknowthatitlookslikethevacuumcleanerissmilingtheyseemedtorealizeitwasamachineandnotaperson.OlsontoldDailyMail.Theeffectgoesaway.Thisseemstobehappeningonaverysubconsciouslevel. Researchersbelievetheresultsarcimportantforconsumerstorealizehowthesetypesofproductscouldaffecttheirsocialinteractionwithrealpeopleespeciallybecausesomanynewproductsfeatureinteractivity. lfsomeonenoticestheyaretalkingmoretoSirilatelymaybethathassomethingtodowithfeelinglonely.Olsonsaid.Fromthatstandpointit'simportanttobeawareofit. Thestudycouldalsohelpcompaniesdesignproductsthatcanincreasethewell﹣beingofpeoplewhofeellonelywithoutsacrificingnormalsocialinteraction. Maybeiiismoreaboutimprovingourcurrentrelationships.Olsonsaidsuchastakingabreakfromscreentimeandfocusingondevelopingyourrealpersonalconnections. 56.ResearchersfromtheUniversityofKansasfoundthat. A.hunum﹣likedevicesmayhelppeopleinteractwithothers B.interactionswithhuman﹣likedevicesmaymakepeoplefeellonely C.lonelypeoplemayeasilybecomeaddictedtohuman﹣likedevices D.human﹣likedevicesmayreducepeople'ssocialinteractioninreallife 57.Duringtheexperimentsparticipants. A.wereallowedtotalkwithhuman﹣likedevices B.wereshowndeviceswithhumanfeatures C.playedonlinegameswithbothmachinesandrealpeople D.wereencouragedtoengageinnormalhumaninteraction 58.TheunderlinedphrasethiseffectinParagraph7referstothefactthat A.lonelypeoplearemorelikelytoseekoutinteractionwithotherpeople B.lonelypeoplearecontenttointeractvviihhuman﹣likemachines C.thefeelingoflonelinessdeepensaspeopleinteractwithhuman﹣likedevices D.peoplewhoaresociallyexcludedwillhavedifficultyinsocializing 59.Oneofthesignificancesofthestudyisthatit. A.showspeoplewhyhuman﹣likeproductsmakethemfeellonely B.warnspeopletoabandonhuman﹣likedevicescompletely C.forceslonelypeopletogetinvolvedinnormalsocialinteraction D.helpcompaniesrealizethelimitationofhuman﹣likedevices.
AstudybySanDiegoZooGlobalconservationistsreleasedthisweekSept.122016issheddingnewlightonhowscientistsevaluatepolarbeardietandweightlossduringtheirfasting禁食season.Onaverageapolarbearlosesupto30percentofitstotalbodymass体重whilefastingduringtheopen﹣waterseason.Althoughsomescientistspreviouslybelievedland﹣basedfoodscouldsupplement补充thebears'nutritionalneedsuntiltheseaicereturnsanewstudypublishedinthescientificjournalPhysiologicalandBiochemicalZoologyhasrevealedthataccesstoterrestrialfoodisnotsufficienttoreducetherateofbodymasslossforfastingpolarbears. Thestudy﹣﹣undertakenbyManitobaSustainableDevelopmenttheUniversityofAlbertaandEnvironmentandClimateChangeCanada﹣﹣weighedpolarbearsthatweredetainedinthePolarBearHoldingFacilityinChurchillManitobaCanadafrom2009to2014.PolarbearswerekeptinthisfacilityaspartofthePolarBearAlertProgramwhichaimstoreduceconflictbetweenhumansandpolarbearsaroundthetownofChurchill.Topreventhabituationpolarbearsarenotfedwhileinthefacilitywhichallowedforacontrolledmeasureoftheirweightloss.Onaveragepolarbearslost2.2pounds1kilogramofmassperday﹣﹣exactlythesameamountasfree﹣ranging自由放养的bearsmeasuredduringtheice﹣freeseasononthecoastlineofHudsonBay.Scientistsreportedthatevenwithland﹣basedfoodopportunitiespolarbearslostthesameamountofweight. Somestudieshavesuggestedthatpolarbearscouldadapttoland﹣basedfoodstooffsetthemissingcaloriesduringashortenedhuntingperiodontheicesaidNicholasPilfoldPh.D.leadauthorofthestudyandapostdoctoralassociateinAppliedAnimalEcologyatSanDiegoZooGlobal.Yetourresultscontradictthisasunfedpolarbearsinourstudylostmassatthesamerateasfree﹣rangingbearsthathadaccesstoland﹣basedfood. Researchersalsoestimatedstarvationtimelinesforadultmalesandsubadultsandfoundthatsubadultsweremorelikelytostarvebeforetheiradultcounterparts.SubadultpolarbearshavelowerfatstoresandtheaddedenergydemandsassociatedwithgrowthsaidPilfoldFuturereductionstoon﹣icehuntingopportunitiesduetoseaicelosswillaffecttheyoungerpolarbearsfirst﹣﹣especiallygiventhatthesebearsareless﹣experiencedhunters. 63.Whatisthefindingofthisnewly﹣releasedstudy A.Wildpolarbearsarefacingthedangerofstarvationandextinction. B.Land﹣basedfoodcan'tmeetthenutritionalneedsofwildpolarears. C.Wildpolarbearscanavoidweightlossinaproperlydesignedfacility. D.Traditionalwaystomeasurepolarbeardietandweightlossarenotaccurate. 64.WhichofthefollowingisTRUEaboutthestudy A.ItwasactuallypartofthePolarBearAlertProgram. B.Itaimedtopreventthepolarwildlifefromextinction. C.Itcomparedtheweightlossbetweenunfedandfree﹣rangingpolarbears. D.ltmeasuredtheweightofpolarbearsduringon﹣icehuntingseasons. 65.Theunderlinedwordinthefourthparagraphmeans. A.takeover B.takeup C.makeinto D.makeupfor 66.Thereasonswhysubadultsaremorelikelytosufferduringopen﹣waterseasoninclude. Theyhavelessfatstorage. Theyneedmoreenergyforgrowth. Theylackhuntingopportunities. Theyareslowerinadaptingtoiceloss. A.①②B.③④C.①②③D.②③④
下列相关的量之间的关系符合如图所示图线的是
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教室内的日光灯一般都是由两条竖直平行的吊链吊在天花板上的图甲所示两条吊链竖直平行除了美观外还蕴含着科学道理． 1甲图中ab是挂日光灯的吊链．若以吊链a的固定点O作为支点F甲作为拉力时可将灯视作杠杆．选填“省力”“费力”或“等臂”． 2比较甲图乙图两种悬挂方式甲图吊链受到的拉力大小为F甲乙图吊链受到的拉力大小为F乙则F甲F乙选填“＞”“＝”或“＜”． 3若甲图中b吊链突然断开后日光灯将绕O点转动此时日光灯的重力势能将．选填“增大”“减小”或“不变”．
下列图象有关量化趋势不能正确反映其对应操作的是
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如图所示在厚玻璃筒内放一小团浸有少量乙醚的棉花快速压下活塞观察到棉花燃烧．下列说法正确的是
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Onetrendinappdevelopmentispositivityprogramsdesignedspecificallytohelpretrainourbraintothinkpositively.Hereareourtoprecommendationsforappstoimproveyourpositivemood. ThinkUp Havinga4.7starratingthisappisaheavyhitterintheworldofpositivityapps. Peoplearefindingthattheycanlearntobepositiveandsavetheirlivesfromtheconvenienceoftheirhandhelddevices设备.Wenolongerhavetogotothelibraryandcheckoutbooks.Justdownloadthisfreeappandstartthinkingpositivelyandwatchhowyourlifechanges. Shine Thisappisrecognizedasthebestof2018andithelpsyouwithdailymotivationandpersonalcare.Thisapp'sgoalistohelpreduceyourstresssodon'tworryaboutaddingonemorethingtoyourto﹣dolist.Theysendmotivationaltextsincludingagratitudejournal.Thisisanincrediblewaytechnologyjoinsgreatmindssowecanallimprovetogether! Happler Holdingastrong3.9starevaluationgradethisisonewelove.Itcanhelpyoukeepajournalhasincrediblecoursesandletsyouexchangeideaswithawholecommunityofpeopleworkingtobecomemorepositive.Welovethecreativitythatwentintomakingthisappandthinkithasalottooffer. Motivate Thisappgainsa4.8starratingafterover2622ratingswhichhashandpickedmotivationvideosandmusicplaylistsforanymoodyou'dliketogetinto.Ifyouneedtorelaxorgetenergizedorinspiredtogrowinspecificareasofyourlifethisuniqueappwillhelpyouchooseyourcategoryandgetyouthinkingpositivelyaboutitthroughtheuseofimagesandmusic. 1Whichcanhelpyouwithpersonalcare? A.ThinkUp. B.Shine. C.Happier. D.Motivate. 2Whatdothefourappshaveincommon? A.Theyofferinteractiveteaching. B.Theyenableuserstobemorepositive. C.Theyareallstar﹣rated. D.Theyhelppeoplereachtheirgoals. 3What'sspecialabouttheappMotivate? A.Itgainsthehighestrating. B.Ithelpspeoplekeepajournal. C.Itprovidesvideosandmusic. D.Itsendsmotivationaltexts.
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InanewstudypublishedinjournalJAMAPaediatricsresearchersfoundtheamountoftimethatchildrenundertheageoftwospendlookingatscreensondigitaldeviceshasmorethandoubledovera17﹣yearperiod. Theteamtookalookbackatatimewhenmobilephoneusewasfarlesscommonthanitistodayassessingchildren'sscreentimein1997andthencomparingitto2014. TheresearchersusedstatisticspreviouslygatheredbytheChildDevelopmentSupplementPanelStudyofIncomeDynamicsattheUniversityofMichigananalysingdataregarding1327childrenin1997and443childrenin2014. AccordingtotheirfindingschildrenundertheageoftwointheUSwouldspendanaverageof1.32hoursinfrontofascreenonadailybasisin1997.By2014thisaveragehadincreasedto3.05hoursmorethandoublingover17years.Incomparisonchildrenagedbetweenthreeandfivespentanaverageoftwoandahalfhoursinfrontofscreensonadailybasisin1997.Thishadincreasedslightlytothreehoursadayby2014. ThereisgrowingconcernovertheamountoftimethatchildrenparticularlyveryyoungchildrenspendwatchingshowsandinfrontofscreenssaidWeiweiChenassistantprofessorintheDepartmentofHealthPolicyandManagement.Ourfindingsweresurprisingasitfeelslikemobiledevicesareeverywherebuttelevisionsarestillthemostcommonwayforyoungchildrentoconsumemedia.Furtherresearchisneededtoassesschangesinmediaconsumptionanddeviceuseinmorerecentyears. Expertswarnedthatvulnerablechildrencouldfacebecominglostindigitalspaceasthey'regrowingupwithoutenoughInternetsafetyeducation. 1Whatcanweknowaboutthenewstudy? A.Ittook17yearstoconduct. B.Itincludedchildrenbornin1997. C.Itcomparedstatisticsfromtwodifferentperiods. D.Itwasdonebytwoorganizationsworkingtogether. 2Howdidthedailyscreentimeofchildrenbetween3and5change? A.Italmostdoubled. B.Itreducedslightly. C.Itreached2.5hours. D.Itsawasmallchange. 3Whatsurprisedtheresearchers? A.ChildrenspentmoretimeonTVthanonmobiledevices. B.Digitaldevicesgainedmorepopularityamongchildren. C.Childrenstaredatscreensformuchlongerthanbefore. D.Digitaldevicesfailedtoattractyoungchildren. 4Whatisthebesttitleforthetext? A.ScreenTimeDamagesChildren'sHealth B.NewMethodsFoundtoReduceScreenTime C.ParentsInstructedtoLimitChildren'sScreenTime D.ChildrenunderTwoSpendTwiceLongeronScreens
课外活动即第二课堂是我们自由发展才智的新天地某课外活动小组在实践调查时发现了下列一些现象你认为其中合理的是． A用甲醛溶液浸泡水产品可以起到防腐作用 B现代农业按照国家标准适量使用化肥农药 C将工业明胶代替食用明胶添加到老酸奶果冻中 D将工厂的烟囱造高以减少工厂周围的大气污染 E常用钢丝球擦洗铝壶可以使其光亮洁净且耐用 F夜间发现液化气泄漏应先开窗通风不能立即开灯．
2015年春节期间一男孩在排污井盖上燃放鞭炮点燃了排污井内的气体井盖被炸飞男孩被井盖击伤． 【提出问题】排污井内气体的主要成分是什么 【查阅资料】排污井内的有机物在一定的条件下发酵产生了气体其成分可能含有COCO2CH4等． 【提出猜想】某兴趣小组同学对排污井内气体含有上述气体中最少2种成分的猜想如下 猜想Ⅰ有CO2CH4猜想Ⅱ有COCH4 猜想Ⅲ有COCO2猜想Ⅳ有COCO2CH4 【实验方案】小组同学共同设计了如图所示的装置并经行探究． 【问题讨论】 ①装置A出现浑浊证明猜想不正确． ②小明通过装置C处的现象证明猜想Ⅲ不成立．小芳对此提出了疑义小芳认为要在位置再增加一个图中填序号装置才能证明猜想Ⅲ不成立． ③小明认为要证明排污井内气体是否含有CO可以不用装置B小芳则认为需要使用装置B你认为装置B的作用是．
学校举行运动会小明同学在跳远运动的几个阶段如图所示则他
小乐利用长宽和厚度均相同的锌片铁片与铜片完成了以下实验 利用锌片和铜片制作电池 1小乐从课本中得知将一块锌片和一块铜片插入稀硫酸就可以组成一个电池铜片和锌片是电池的两个电极且溶液中部分离子移动的方向和电极上电子移动的方向如图乙所示．此电池的能量转化是若要用电压表测此电池的电压则电压表的负接线柱应与相连选填“铜片”或“锌片” 2小乐从课本中还知道若在水果中插入锌片和铜片可以制得水果电池于是她完成了 如下实验 通过上述实验可知水果电池电压大小的影响因素有．
易拉罐拉环拉断后就很难打开若将A4纸对折几次后用纸的硬尖角摩擦原拉环边缘如图所示一会儿罐口就会自动冲开并看到一团“白汽”．出现这团“白汽”是因为水蒸气发生了选填“液化”或“汽化”现象．摩擦后罐口会自动冲开是因为罐内气体对罐口拉片压力增大使罐口打开．
A.changingB.availableC.exposureD.worsenE.sensitive F.densityG.restH.shadedI.refleciionsJ.interruptedK.fighting Areyoureyesdrywateryseeingdoubleor31tolightanddoyourbackandneckacheIfsoyouarelikelyoneofmanypeopletodaywhosufferfromdigitaleyestrain视疲劳alsocalledcomputer﹣visionsyndrome. Eyestrainisoftenrelatedtotheamountof32toscreensthedistancefromeyestoscreensandtheuseofmultiplescreensatthesametime.Howeverstudies havealsoshownthatthebluelightproducedbydigitaldevicesreachesfurtherintotheeyesthanotherkindsoflight.Thislightactuallyassisisattentionduringthedaybutcanresultin33sleeppatternsatnight. Scientistshavestatedthateyestrainisnotanecessaryevileveninamodernworldthatcirclesaroundtechnology.Sometimes34somesimpledetailsaboutyourrelativepositiontoscreenssuchasslayingabout60centimetersawaywillhelp.Alsoavoidoverheadandotherdirectsourcesoflightanduse35lampsandwindowblindswhilelookingatdigitaldevicesinstead. Beyondthewaysthatyourelatetodigitalscreenstherearealsowaystochangehowyouviewscreensthatarehelpfulin36eyestrain.Tobeginwithyourcomputerscreenshouldbehigh﹣resolution高分辨率andmayrequireascreentodecrease37.Alsobeawarethat''computerglasseswhichcutdownglare刺眼的光}andbluelightare38onthemarkect. Finallymanyofusfallintobadhabitswhileusiugdigitalscreensthatonly39theeffectsofeyestrain.Whenviewingdigitalscreensmanypeopleblink眨眼onethirdlessoftenthantheyusuallydo.Placeareminderonyourcomputertoblink!sothatyoureyesdon'tdryout.Also40youreyes'focusingmusclesbyusingthe20﹣20﹣20ruleevery20minutesfocusonsomething20feetawayfor20seconds. Therearemanyothermethodsusedtohelprelieveeyestrainsofindwhatworksforyouratherthangivingintotiredvision.
“珍爱生命远离毒品”．__是一种毒品能引发急性心脑疾病并出现狂躁暴力自杀等倾向其主要成分为甲基苯丙胺化学式为C10H15N．下列有关甲基苯丙胺的说法正确的是
WiththeaveragenumberofchildreninaBritishfamilyfallingunderanaverageof2.0comparedwiththetraditional2.4childrenthepopulationoftheUKhasbeenfallingforquiteafewyears. Whyaren'tBritishpeoplehavingasmanychildrenastheyusedtoWelltherearemanyreasons.OneofthemisthatBritishpeoplearenowhavingtheirchildrenatamucholderagethanpreviouslymeaningtheyhavefeweryearsinwhichtheycanhavechildren.Mostyoungpeopletodaywantawell﹣paidjobsotheyoftengotouniversityafterhighschoolafteryearsofstudyatuniversitytheythenneedafewyearsofworkexperiencebeforetheycangetthejobtheywant.Soit'snotuntiltheyareabout30yearsoldthattheycanstarttothinkaboutsettlingdownandhavingchildren. AnotherreasonisthatitisrelativelyexpensivetobringupachildintheUK.Usuallybothparentsneedtoworktopayfortheirhomeandlivingexpenses.Theyneedtopaysomeonetolookaftertheirchildduringthedaywhichisexpensive. InadditionproblemsintheglobaleconomyoftenaffectBritishfamilies.Forexamplewhentimesaretoughandthereisaneconomicdownturnitbecomesdifficulttofindajoborkeeptheexistingone.Thiskindofuncertaintydiscouragespeoplefromhavinglargerfamilies. SowhatisBritaindoingtotryandsaveBritishfamiliesFirstofallthegovermmentistryingtomakeitcheapertohavechildren.Forexampletherehavebeenincreasesinmoneyfamiliescangainfromthestateeachmonth.Alsothereisanincreasingamountofmoneyfornurseryschoolssothatparentsdon'tneedtopaysomuchforchildcare.Inadditiontherearenowlawsallowingparentstotakemoretimeoffworksothattheycanlookaftertheirchildrenthemselvesratherthanhavingtopayotherstodoit. .
小金用图示装置探究平面镜成像特点．实验探究的步骤如下 A．在水平桌面上铺一张白纸将一块玻璃板竖立在纸上在纸上记下玻璃板的位置． B．选取两支大小相同的蜡烛把一支蜡烛点燃放在玻璃板的前面看到玻璃板后面有蜡烛的像时在纸上记下蜡烛的位置A． C．拿另一支没有点燃的蜡烛竖立着在玻璃板后面移动直到它与前面的蜡烛的像完全重合在纸上记下该蜡烛的位置A′． D．移动点燃的蜡烛到另一位置重做上面的实验在纸上记录物与像的位置BB′CC′． 1刚开始小金在做步骤C时无论怎么移动蜡烛都无法使它与前面的蜡烛的像完全重合．请分析产生这一现象的可能原因．经过改正后小金重新实验． 2步骤D的实验目的是 3图乙是物像的位置实验记录请你利用测量工具对乙图的实验记录作出处理并得到相应规律．
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