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在学习了浮力的有关知识后，甲、乙两名同学对“物体的上浮或下沉与哪些因素有关”进行了探究．他们各自将一根新鲜萝卜浸没在水中，松手后，发现萝卜上浮直至漂浮在水面上（如图①甲所示）．为了使漂浮的萝卜沉下去...
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右图是探究影响浮力大小因素的实验1由甲乙两图可知物体在水中受到的浮力是__________N.乙图中
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在学习认识浮力这节课上同学们看到老师将一木块没没在水中放手后木块先上浮最终漂浮在水面上．请你利用物
小伟在学习了浮力知识后做了如图所示的实践活动在同一水平桌面上的两个相同容器分别盛有甲乙两种液体将同一
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10分Asachildgrowsupyoumaywonderhowyoucanteachhimtobecomearespectfuladult.1Achildwholearnstorespectnotonlylearnstoreceiverespectfromothersinkindbutalsolearnstorespecthimself. ●Showhimrespect. Thisisthebestwaytoteachyourchildhowtorespectothers.Listentoyourchildattentivelyandhewilllearntolistentoyouunderstandinghowimportantthisisincommunication. ●2 Themoreyousaypleaseandthankyoutoyourchildthemorelikelyhewilllearntousethem.Politenessthenbecomesanormalpartofanyconversation. ●Agreetodisagree. 3Explainyourdecisionsothathewillunderstandyouandexpectrespectfulresponses.Disagreeingwithyoudoesn'tnecessarilymeandisobedience不顺从. ●Controlyourimpulsetooverreact. Whenasituationarisesstaycalmandkeepinmindthatyouaresupposedtobemodelingcorrectbehavior.4 ●Praisepraisepraise Somuchisfocusedonwhatachilddoeswrongandhowtocorrectitthathisaccomplishmentsarenotcelebratedenough.5 A.Teachmannersbyusingpoliterequestsandresponses. B.Trytorememberthatachildwon'talwaysagreewithyou. C.Respectisnecessaryforameaningfulandsuccessfullife. D.Ifheseesyouloseyourtemperheismorelikelytorespondthatwayinfuture. E.Achildmayactashepleasesandhewillliveahappylife. F.Seeingachildexhibitrespectfulbehaviormakesureheknowshowproudyouareofhim. G.Respectfulbehaviorisalwaysaccompaniedbybadbehaviorasachild. 1. 2. 3. 4. 5.
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碘是生命体中的必需元素请根据如下有关碘及其化合物的性质回答下列问题 1实验室中制取少量碘可采用如下方法KI+CuSO4→A白色↓+K2SO4+I216.0gCuSO4与过量KI反应后可得19.1g的A写出A的化学式． 工业生产中可用智利硝石含有NaIO3为原料与NaHSO3反应后生成碘写出此反应的离子方程式． 2单质碘与氟气反应可制得IF5实验表明液态IF5具有一定的导电性研究人员发现产生这一现象的可能原因在于IF5的自偶电离如2H2O⇌H3O++OH﹣生成的阳离子为阴离子为． 3将单质碘与铝屑置于管式电炉中隔绝空气加热至500℃得到棕色片状固体此固体溶于Na2CO3溶液可产生白色沉淀和气体．请写出上述实验过程中发生的化学反应方程式． 4试设计实验方案判断加碘食盐中碘的存在形式I﹣IO3﹣或两者同时存在．已知5I﹣+IO3﹣+6H+＝3I2+3H2O
1分Afriendwithout缺点willneverbefound.
10分 Howtowriteanewsstory Writingnewsstoriesisn'tverydifficult.Itdoestakepracticeandnoteveryonewillbeanexpertbutifyoufollowtheguidelinesbelowyou'llfinditisnotthatdifficult. ThefiveWsandtheH Who?What?Where?When?Why?How? 1Ifyouwishtocoverastoryaboutalocalsportsteamenteringacompetitionyouwillneedtoanswerthesequestions: ●Whoistheteam? ●Whatsportdotheyplay? ●Whereisthecompetition? ●2 ●Whyaretheyenteringthisparticularcompetition? ●Howaretheygoingtoenterthecompetition? Theinvertedpyramid倒金字塔 Thisreferstothestyleofjournalismwhichplacesthemostimportantfactsatthebeginningandworksdownfromthere.3Itshouldcoverenoughinformationtogivethereaderagoodviewofthewholestory.Therestofthearticleexplainsandexpandsonthebeginning. Moretips ●It'saboutpeople. Newsstoriesareallabouthowpeopleareaffected.Inyoursportsstoryyoumightspendsometimefocusingononeormorepersonsorhowthesupportersarefeeling. ●4 Youshouldnotsupportanyofthesidesinvolvedinastory.Ifthereismorethanonesidetothestorycoverthemall. ●Don'tgetflowery. 5Don'tuselotsofheavilydescriptivelanguage.Whenyou'vefinishedgothroughthewholestoryandtrytoremoveanywordswhicharen'tnecessary. A.Whenisthecompetition? B.Howlonghavetheybeenpreparing? C.Don'tbeinfluencedbypersonalbeliefs. D.Keepyoursentencesandparagraphsshort. E.Thefirstparagraphisusuallyveryimportant. F.Anygoodnewsstoryprovidesanswerstoeachofthesequestions. G.Thestorymightbecutoff删除atanypointbecauseofspacelimitations. 1. 2. 3. 4. 5.
8分 AGuidetotheUniversity Food TheTWUCafeteriaisopen7amto8pm.Itservessnacks小吃drinksicecreambarsandmeals.YoucanpaywithcashoryourIDcards.YoucanaddmealmoneytoyourIDcardsattheFrontDesk.Evenifyoudonotbuyyourfoodinthecafeteriayoucanusethetablestoeatyourlunchtohavemeetingsandtostudy. IfyouareoncampusintheeveningorlateatnightyoucanbuysnacksfastfoodanddrinksintheLowerCafélocatedinthebottomleveloftheGouglasCentre.ThisareaisoftenusedforentertainmentsuchasconcertsgamesorTVwatching. Relaxation TheGlobelocatedinthebottomlevelofMcMillanHallisavailableforrelaxingstudyingcookingandeating.Monthlyactivitiesareheldhereforallinternationalstudents.Hoursare10amto10pmclosedonSundays. Health LocatedonthetopfloorofDouglasHalltheWellnessCentreiscommittedtophysicalemotionalandsocialhealth.Adoctorandnurseisavailableifyouhavehealthquestionsorneedimmediatemedicalhelporpersonaladvice.Thecostofthisisincludedinyourmedicalinsurance.HoursareMondaytoFriday9amtonoonand1:00to4:30pm. AcademicSupport AllstudentshaveaccesstotheWritingCentreontheupperfloorofDouglasHall.Herequalifiedvolunteerswillworkwithyouonwrittenworkgrammarvocabularyandotheracademicskills.Youcansignupforanappointmentonthesign﹣upsheetoutsidethedoortwo30﹣minuteappointmentsperweekmaximum.Thisserviceisfree. Transportation TheTWUExpressisashuttle班车service.TheshuttletransportsstudentsbetweencampusandtheshoppingcentreleavingfromtheMattsonCentre.Operationhoursarebetween9amand3pm.Saturdaysonly.Roundtripfareis$1. 1.WhatcanyoudointheTWUCafeteria? A.DohomeworkandwatchTV. B.Buydrinksandenjoyconcerts. C.Havemealsandmeetwithfriends. D.AddmoneytoyourIDandplaychess. 2.Whereandwhencanyoucookyourownfood? A.TheGlobeFriday. B.TheLowerCaféSunday. C.TheTWUCafeteriaFriday. D.TheMcMillanHallSunday. 3.TheGuidetellsusthattheWellnessCentre. A.isopensixdaysaweek B.offersservicesfreeofcharge C.trainsstudentsinmedicalcare D.givesadviceonmentalhealth 4.HowcanyouseekhelpfromtheWritingCentre? A.Byapplyingonline. B.Bycallingthecentre. C.Byfillinginasign﹣upform. D.Bygoingtothecentredirectly.
复数z满足z1﹣i＝|1+i|则复数z的共轭复数在复平面内的对应点位于
常温下向20mL0.2mol/LH2C2O4溶液中滴加0.2mol/LNaOH溶液．有关微粒的物质的量变化曲线如图所示[已知CaC2O4难溶于水]．根据图示判断下列说法不正确的是
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