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水体砷污染已成为一个亟待解决的全球性环境问题，我国科学家研究零价铁活化过硫酸钠（Na2S2O8）去除废水中的正五价砷[As（Ⅴ）]，其机制模型如图． 资料： Ⅰ．酸性条件下SO42﹣为主要的自...
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高三下学期化学《》真题及答案
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温室效应引起的全球变暖已成为人类关注的焦点最近澳大利亚科学家研究后指出与全球变暖相伴随的还有全球变暗
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原创关于环境问题说法不正确的是
大气圈、水圈、岩石圈、生物圈等人类赖以生存的环境遭到污染，已成为全球性的问题
发达国家的环境问题十分严重，发展中国家不存在环境问题
环境问题是伴随着人口、资源、发展问题出现的，其实质就是发展问题
世界环境问题的解决要依赖发达国家和发展中国家携手共同努力
当前国际社会最为关注的全球性大气环境问题主要是
温室气体增多、可能导致全球变暖、臭氧层遭破坏和酸雨
大气污染、水体污染、固体废弃物污染
人口增多、资源枯竭、森林锐减
水源短缺、粮食缺乏、噪声污染
下图为生物界氮循环的示意图请回答下列问题目前粮食短缺已成为全人类面临的一个重大危机因此科学家们设想让
保护环境已成为当前和未来的全球性重大课题之一下列因人类生产生活对环境破坏而带来后果的是①土地沙漠化②
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全部
温室效应引起的全球变暖已成为人类关注的焦点最近澳大利亚科学家研究后指出与全球变暖相伴随的还有全球变暗
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保护环境已成为当前和未来全球性的重大课题之一为了消除对大气污染有科学家提出利用太阳能促使燃料循环使用
CO2
CH3OH
N2
H2O
长期以来人们认为砷元素含有剧毒会对生命构成严重威胁然而科学家经过研究实验发现一种新的细菌能够利用剧毒
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第二节书面表达满分25分今年是世界环境保护年请根据下面要点写一篇短文谈谈你对污染的看法100-120
我国的南极科考队员发现南极地区部分海冰融化导致企鹅的栖息地正在减少科学家认为这是由于________
水土流失
荒漠化
全球气候变暖
大气污染
我国的南极科考队员发现南极地区部分海冰融化导致企鹅的栖息地正在减少科学家认为这是由于这一全球性环境问
水土流失
荒漠化
全球气候变暖
大气污染
下列环境问题的叙述不正确的是
环境问题主要表现为环境污染和生态破坏
各国所面临的环境问题是相同的
环境问题已经发展成为全球性的问题
解决酸雨、全球变暖等环境问题必须进行国际合作
环境问题已成为全球普遍关注的问题下列与环境污染无关的是①温室效应②赤潮③酸雨④光化学污染⑤臭氧空洞⑥
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在全球能源高度紧张的今天应用超导技术降低能耗已成为许多科学家研究的新课题这表明
实践是认识发展的根本动力
认识世界是实践的最终目的
技术完全是科学家研究的结果
科学实验是获得认识的唯一途径
近代工业的发展过程中由于人类过度追求经济增长速度而忽略环境的重要性导致水土流失土地沙漠化水体污染空气
大气污染问题
饮用水问题
温室气体问题
环境问题
我国设施园艺亟待解决的问题是什么
水体污染已成为严重的环境问题．请你写出一条水体被污染的原因并设计一种实验检验某化工厂排放的废水显酸
防止环境污染保持生态平衡目前已成为工业国家的一个重要的社会趋势
白色污染是人们对塑料垃圾污染环境的一种形象称谓白色污染的危害有侵蚀土地污染空气污染水体火灾隐患等由于
当前我国环境保护亟待解决的白色污染问题指的是
石灰窑的白色粉尘
火电厂的白色烟尘
聚乙烯等塑料垃圾
白色建筑材料
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AnexperimentalcleanupdevicecalledRemoveDEBRIShassuccessfullycastanetaroundadummy仿真的satelliteimitatingatechniquethatcouldonedaycollectspacebornegarbage. ThetestwhichwascarriedoutthisweekiswidelybelievedtobethefirstsuccessfuldemonstrationofspacecleanuptechnologyexpertstoldCNN.Anditsymbolizesanearlysteptowardsolvingwhathasalreadybeenacriticalissuejunkinspace. Millionsofpiecesofjunkareturningaroundinorbittheresultof50yearsofspacetravelandfewregulationstokeepspaceclean.Atorbitalspeedsevenasmallbitofpaintcrashingwithasatellitecancausecriticaldamage. Variouscompanieshaveplanstosendthousandsofnewsatellitesintolow﹣Earthorbitalreadythemostcrowdedarea. TheRemoveDEBRISexperimentisrunbyacompanyandresearchersledbytheU.K.'sSurreySpaceCenterandincludesAirbusAirbus﹣ownedSurreySatelliteTechnologyLtd.andFrance'sArianeGroup. GuglielmoAgliettithedirectorofSurreySpaceCentersaidthatanoperationalversionoftheRemoveDEBRlStechnologywouldcastanetthatremainsfastenedtothemainsatellitesothedebriscanbedraggedoutoforbit.Itcouldtargetlargepiecesofjunkincludingdeadsatellitesupto10meterslong. TheRemoveDEBRISsatellitewillconductafewmoreexperimentsinthecomingmonthsincludingtestingnavigationfeaturesthatcouldhelpguidethesatellitetoaspecificpieceofdebris. Therearestillenormousbarrierstoclearbeforeoperationalcleanuptasksareunderwayhesaidandthemostdiscouragingisfiguringouthowtofundsuchprojects. AgliettitheSurreyprofessorwhohelpedleadtheRemoveDEBRISprojectsaidThechallengewilllieinpersuadingtherelevantauthoritiestosponsorthesetasks.AgliettisaidhehopesRemoveDEBRISwillconductafewcleanuptasksperyeartargetingthelargestpiecesofjunkinthemostcrowdedorbits. 1WhatistheuseoftheRemoveDEBRISsatellite? A.Disposingofspacewastes. B.Demonstratingspacetechnology. C.Imitatingadevelopingtechnique. D.Solvingseriousjunkproblemsinspace. 2HowdoestheRemoveDEBRlSsatellitework? A.Bythrowinganettotakethejunkfromorbit. B.Byfasteningittothemainsatellitetightly. C.Bydraggingsatellitesupto10meterslong. D.Bytargetinglargepiecesofjunkcarefully. 3Whatdoestheunderlinedwordsponsorinthelastparagraphprobablymean? A.Accomplish. B.Support. C.Oppose. D.Provide. 4What'sthebesttitleforthetext? A.ACriticalIssueJunkinSpace B.HowRemoveDEBRISIsDeveloped C.WhytheRemoveDEBRISSatelliteIsInvented D.SatelliteCollectsSpaceJunkfortheFirstTime
已知l1x﹣my+3＝0l2x+y+1＝0若l1∥l2则m＝
已知数列{an}的通项公式an＝n∈N*Sn为数列{an}的前n项和满足Sn＞9n∈N*则n的最小值为
IfEnglishmeansendlessnewwordsdifficultgrammarandsometimesstrangepronunciationyouarewrong.Haven'tyounoticedthatyouhavebecomesmartersinceyoustartedtolearnalanguage? AccordingtoanewstudybyaBritishuniversitylearningasecondlanguagecanleadtoanincreaseinyourbrainpower.Researchersfoundthatlearningotherlanguageschangesgreymatter.Thisistheareaofthebrainwhichprocessesinformation.Itissimilartothewaythatexercisebuildsmuscles. Thestudyalsofoundtheeffectisgreaterwhentheyoungerpeoplelearnasecondlanguage.AteamledbyDr.AndreaMechellifromUniversityCollegeLondontookagroupofBritonswhoonlyspokeEnglish.Theywerecomparedwithagroupofearlybilingualswhohadlearntasecondlanguagebeforetheageoffiveaswellasanumberoflaterlearners.Scansshowedthatgreymatterdensity密度inthebrainwasgreaterinbilingualsthaninpeoplewithoutasecondlanguage. ProfessorDylanVaughanJonesoftheUniversityofWaleshasresearchedthelinkbetweenbilingualismandmathsskills.Havingtwolanguagesgivesyoutwowindowsontheworldandmakesthebrainmoreflexible灵活的hesaid.Youareactuallygoingbeyondlanguageandhaveabetterunderstandingofdifferentideas. ThefindingswerematchedinastudyofnativeItalianspeakerswhohadlearnedEnglishasasecondlanguagebetweentheagesoftwoandthirty﹣four.Readingwritingandcomprehensionwerealltested.Theresultsshowedthattheyoungertheystartedtolearnthebetter.Studyingalanguagemeansyougetanentrancetoanotherworldexplainedthescientists. 1Whatisthemainsubjecttalkedaboutinthispassage? A.Languagelearningcanhelpbrainpower. B.Man'sabilityoflearningasecondlanguage. C.Scienceonlearningasecondlanguage. D.Languagelearningandmathsstudy. 2Whydoesthewritermentionexerciseinthesecondparagraph? A.Tosaylanguageisalsoakindofphysicallabor. B.Tomakepeoplebelievelanguagelearninghelpsgreymatterworkwell. C.Toshowtheimportanceofusingthelanguagewhenyoulearnthelanguage. D.Toprovethatoneneedsmorepracticewhenhesheislearningalanguage. 3Whatdoestheunderlinedwordbilingualprobablymeaninthethirdparagraph? A.aresearcheronlanguagelearning B.asecondlanguagelearner C.apersonwhocanspeaktwolanguages D.anactivelanguagelearner 4Whatdoestheauthorwanttotellusbythelasttwoparagraphs? A.Learningasecondlanguageisthesameasstudyingmaths B.You'dbetterchoosetheagesbetween2and34tolearnasecondlanguage C.Italianisthebestchoiceforyouasasecondlanguage D.Earlylearningofasecondlanguagehelpsyouagreatdealinstudyingothersubjects
设实数xy满足则z＝x﹣y的最大值是
假定你是红星中学的李华你的英国朋友Peter热爱体育运动他将作为交换生到你校学习一年.请你给他写封邮件主要内容包括 1.介绍你校体育课程及活动 2.推荐一项中国传统体育项目. 注意1.词数100左右 2.可以适当增加细节以使行文连贯.
线粒体是有氧呼吸的主要场所．科学家在研究线粒体组分时首先将线粒体放在低渗溶液中获得涨破的外膜经离心后将外膜与线粒体内膜包裹的基质分开．再用超声波破坏线粒体内膜破裂的内膜自动闭合成小泡然后用尿素处理这些小泡实验结果如图1所示．请分析回答下列有关问题 1研究发现线粒体内膜蛋白质含量高于外膜原因是．用超声波破坏线粒体内膜破裂的内膜自动闭合成小泡说明生物膜结构具有性的特点． 2图中含F0﹣F1颗粒的内膜小泡有可能完成有氧呼吸第阶段的反应． 3线粒体内膜上的F0﹣F1颗粒物是ATP合成酶如图2所示其结构由突出于膜外的亲水头部和嵌入膜内的疏水尾部组成其功能是在跨膜H+浓度梯度推动下合成ATP． ①为了研究ATP合成酶的结构与合成ATP的关系用尿素破坏内膜小泡将F1颗粒与小泡分开检测处理前后ATP的合成．若处理之前在具有跨膜H+浓度梯度的条件下含颗粒内膜小泡能合成ATP处理后含颗粒内膜小泡不能合成ATP说明F1颗粒参与催化ATP的合成． ②ATP合成酶在植物细胞中还可能分布于膜上．
Bookstoresareatraveller'sbestfriendstheyprovideconvenientshelterinbadweatherandtheyoftenhostreadingsandotherculturalevents.Hereisalookattheworld'ssixgreatestbookstores. AdrianHarrington﹣since1971.Rarebooksrarefirsteditionsleather﹣boundsetsandgeneralantiques古玩.Address64AKensingtonChurchStreetKensingtonLondonEnglandU.K. AnotherCountry﹣KreuzbergBerlinGermany.AnotherCountryisanEnglishlanguagesecond﹣handbookshopwhichismostlyusedasalibrary.Theyhaveabout20000booksthatyoucanbuyorborrow.Someregulareventsareheldattheshopsuchasreadingsculturaleventssocialeveningsandfilmnights. AtlantisBooks﹣OiaSantoriniGreece.AtlantisBooksisanindependentbookshopontheislandofSantoriniGreecefoundedin2004byagroupoffriendsfromCyprusEnglandandtheUnitedStates.Throughouttheyearithashostedliteraryfestivalsfilmscreeningsbookreadingsandgoodold﹣fashioneddanceparties. Bart'sBooks﹣OjaiCaliforniaU.S.A.TheWorld'sGreatestOutdoorBookstoreabookstorefoundedbyRichardBartinsdalein1964.Shelvesofbooksfacethestreetandregularcustomersareaskedtodropcoinsintothedoor'scoinboxtopayforanybookstheytakewheneverthestoreisclosed. 10CorsoComo﹣MilanItalyExtensiveselectionofpublicationonartarchitecturedesigngraphicsandfashionalongwithastrongemphasisonphotography.Itwasfoundedin1990inMilanItalybyCarlaSozzani. TheBookworm﹣AbookshoplibrarybarrestaurantandeventspacenowwithfivelocationsinthreecitiesinChina﹣BeijingSuzhouandChengdu.Theinterconnectingroomswithfloor﹣to﹣ceilingbooksoneverywallarelightandairyinsummeryetwarmandcomfortableinwinter. 1Whatcanlearnabouttheabovebookstores? A.Theyaretraveler'sbestfriends. B.Theyusuallyhostreadings. C.Theyarethegreatestbookstoresintheworld. D.TheyareallinEurope. 2Wherecanwewatchfilmsaccordingthepassage? A.InAnotherCountryand10CorsoComo. B.InAnotherCountryandAtlantisBooks. C.InAtlantisBooksandTheBookworm. D.InAtlantisBooksand10CorsoComo. 3WhatisspecialBart'sBooks? A.Customerscanbuybooksevenafteritisclosed. B.Booksareputinoutdoorshelves C.Ithasthelongesthistoryintheworld. D.Customersshouldpayforbooksincoins.
TheUnitedStatesestimatesthataboutoneoutofevery10peopleontheplanettodayisatleast60yearsold.By2050it'sprojectedtobeoneoutof5.Thismeansthatnotonlywilltherebemoreoldpeoplebuttherewillberelativelyfeweryoungpeopletosupportthem. ProfessorRichardLeeoftheUniversityofCaliforniaatBerkeleysaysthisagingoftheworldhasagreateffectoneconomics.Populationagingincreasestheconcentrationofpopulationintheolderagesandthereforeitisexpensivehesaid. Agingpopulationsconsume消耗moreandproduceless.Withmorepeoplelivinglongeritcouldgelexpensive.ButMr.Leesayswithcontinuingincreasesinworkerproductivityandwiseplanningitcanbemanageable. SocietieshavedifferentmethodsforcaringfortheelderlybuteachcarriesacostGenerallytherearethreetypesofsupportSeniorscanliveoffthewealththeygainedwhentheywereyounger.Theycanrelyontheirfamilytotakecareofthemortheycanrelyonthemovement. Inindustrializednationsgovernmentscreatedpublicly﹣funded公共资助的supportsystems.TheseworkedrelativelywelluntilrecentyearswhenagingpopulationgrowthinplacesliketheUnitedStatesandWesternEuropebegantograduallyweakenthesystems'finances资金.Thesenationsnowfacesometoughchoices.Mr.Leesaystheelderlyinsomeofthesecountriesmusteitherreceivelessmoneyretirelaterorincreasetaxestomakethesystemcontinuable. Mostdevelopingnationshaven'tbuiltthistypeofgovernment﹣fundedsupportbuthaveinsteadreliedonfamiliestocarefortheirelderly.Thesenationsalsogenerallyhaveamuchyoungerpopulationwhichmeanstheirsituationisnotasurgentasmoredevelopednations.ButMr.Leesaysthatdoesn'tmeantheycanpatnoattentiontheissue.ThirdWorldcountriesshouldgiveverycarefulthoughttothisprocesstopopulationagingandhowitmayaffecttheireconomies﹣nowbeforepopulationagingevenbecomesanproblemheexplained. 1Whatisoneofthelikelyresultsofpopulationagingaccordingtothepassage? A.Therewillbemoreoldpeoplethanyoungones. B.Morethan20%ofpeoplewillbeatleast60yearsold. C.Itwillbemoredifficulttosupportoldpeople. D.Theworld'sconcentrationwillbeonoldpeople. 2WhatdoesProfessorLeethinkoftheproblemofpopulationaging? A.Itislikelytomanageit. B.Itistooexpensivetosolveit. C.Itdependsonhowmuchtheoldgainedwhenyoung. D.Itdependsonthewealthofthewholesociety. 3Whatproblemdothepublic﹣fundedsupportsysteminindustrialnationsface? A.Theyfacetoughchoice B.Thereisnotenoughmoneytosupporttheold. C.Taxesaretoolow. D.Theirpopulationsgrowtooquickly. 4Whichofhefollowingaboutdevelopingcountriesistrue? A.Sofartheireconomieshaven'tbeengreatlyaffected. B.Theirgovernmentgivemoremoneytosupporttheold. C.Theyneedn'tpayattentiontoagingpopulation. D.Theirsituationisalsoserious.
假设你是李华Harry是你的美国笔友.在来信中谈到他学校的图书馆.你常常去你校的图书馆.于是你回信向他介绍这个图书馆.内容包括 1.图书馆的建筑简介如面积层高位置等 2.藏书册数及图书种类. 3.服务项目图书的借阅教师及学生阅览室. 注意 1.信的开头已为你写好 2.词数100左右. 3.可以适当增加细节以使行文连贯. DearHarry Howarethingsgoingwithyou?TalkingaboutlibrariesIwouldliketointroducetoyouaboutourschoollibrary. Bestwishes Yours LiHua
在△ABC中角ABC的对边分别为abc面积为S满足2S+ab＝a+b2﹣c2则tanC＝．
KolbieSandersappearedinaFacebookLivevideoshakingabowlfilledwithstrangers'namesandthenchoosingoneatrandom.Thenshe1acardreadingHalieHipsher. The24﹣year﹣oldgirlfromTexas2thatshehadendedherownengagement婚约intheweeksleadinguptoherwedding.Theownersofthevenue场地toldherthatshecould3herreservationforalaterdate4shewasn'tinterestedinusingthevenueforherself.Soshedecidedtogivetheweddingvenue5﹩3500toacouple6togetmarriedwithinaweek. Sandersaskedcouplesonsocialmediatosendheran7withtheirbackstories.Thensheputtheir8inthebowlandpickedoneout.WhenIchosehernameIwasreally9SanderssaidinaphoneinterviewwithTheWashingtonPost. Sanders'postwas10morethan4000times.Soonothersstartedsendinghermessageswantingtohelp.Aweddingphotographer11herservicesabakeryagreedtobakecookiesandsomeoneelse12todothebride'shairandmakeupforthebigday.Itbecameachainreactionofessential13preparationsSanderstoldThePost. HalieHipshercouldnot14bereachedforcommentbyTheWashingtonPost.Butshelaterappearedinherownlivestream直播thankingSandersandtellingherthatsheisWelcometo15thewedding. Sanderssaidshealso16hundredsofmessagesfromdifferentpeople.Whatan17thingyouaredoing!Blessyouandthehappycoupleonepersonwrote.AnotherpersonsaidKolbieyouhavethebestsoul. Sanderssaidthe18hasbeenverystrong.Ifeellikeit'snotasbigofadealaspeoplearemakingitouttobeshesaid.IjusthadthisandIdidn'twantittogoto19.Ireallyfeltitwas20togiveittosomeonewhocoulduseit. 1A.usedup B.madeup C.heldup D.burnedup 2A.explained B.designed C.suggested D.reminded 3A.face B.control C.accept D.keep 4A.Furthermore B.However C.Besides D.Therefore 5A.worthy B.worth C.valuable D.expensive 6A.willing B.proud C.curious D.daring 7A.question B.answer C.tip D.message 8A.jobs B.ages C.names D.cities 9A.confused B.ashamed C.excited D.worried 10A.refused B.shared C.changed D.discovered 11A.examined B.donated C.ordered D.allowed 12A.failed B.pretended C.offered D.managed 13A.meeting B.wedding C.sports D.get﹣together 14A.normally B.actually C.certainly D.immediately 15A.support B.attend C.develop D.demand 16A.recovered B.attempted C.described D.received 17A.powerful B.hopeful C.wonderful D.awful 18A.process B.response C.pressure D.confidence 19A.waste B.improve C.remember D.touch 20A.natural B.successful C.obvious D.equal
ThanksgivingDayisspecialholidayintheUnitedStatesandCanada1. ThanksgivingDayisreallyaharvestfestival.Thisiswhyitiscelebratedinlatefallafterthecropsarein2.OnDecember41619thePilgrimsfromEnglandlandednearwhatisnowCharlesCityVirginia.TheykneltdownandthankedGodfortheirsafejourneyacrosstheAtlantic. 3ThePilgrimslandedatwhatisnowPlymouthMassachusettsin1620.Theyhadadifficulttimeandthefirstwinterwascruel.ManyofthePilgrimsdied.Butthenextyeartheyhadagoodharvest.SoGovernorBradforddeclaredathree﹣dayfeast盛宴.4Everyonebroughtfood. Intimeothercolonies殖民地begantocelebrateadayofthanksgiving.ButittookyearsbeforetherewasanationalThanksgivingDay.DuringtheCivilWarSarahJosephaHalepersuadedAbrahamLincolntodosomethingaboutit.5TodayAmericanscelebratethishappyharvestfestivalonthefourthThursdayinNovember.CanadianscelebrateThanksgivingDayinmuchthesamewayastheirAmericanneighbours.ButtheCanadianthanks﹣givingDayfallsonthesecondMondayinOctober. A.ButoneofthefirstthanksgivingsinAmericahadnothingtodowithagoodharvest. B.HedeclaredthelastThursdayofNovember1863asadayofthanksgiving. C.ThePilgrimswerethosewhocelebratedthefirstThanksgivingDay. D.Familiesandfriendsgathertoeatandgivethanksfortheirblessing. E.ThePilgrimsinvitedIndianfriendstojointhemfortheirspecialfeast. F.ThisiswhyhedecidedtomakeitanationalholidaythroughouttheU.S.. G.ThefirstNewEnglandThanksgivingdidcelebratearichharvest.
Bitcoinandotherso﹣calledcryptocurrencies加密货币havebeenalloverthenewslately.Apparentlytheideaofmoneythat'snottiedtoaspecificbankoraspecificcountryisappealingtomany.Andmoreandmorepeopleshowtheirinterestinthesecryptocurrencies. Inthepastmoney'smakeupvariedfromplacetoplace.Variousobjectshaveservedascurrencyincludingbeadsivoryandshells.InWestAfricabracelets手镯ofbronzeorcopperconsideredtohavegreatworthwereusedascashespeciallyifthebusinesswasassociatedwiththeslavetradethere.ThroughoutthecolonialperiodwhentobaccowasplantedgreatlyandbroughtbigeconomicbenefitsitwasusedinplaceofcoinsorpaperbillsinVirginiaMarylandandNorthCarolina. TodayonMalaitaanislandinthePacificaspecifictypeofshellstillservesascurrencyandsomepeoplethereareevenhoardingitjustlikeBitcoinconvincedthatonedayitwillmakethemwealthybeyondimagination.MaryBrunoashopownerfromthesmalltownofAukionMalaitasaidoneofdarkershellsmightgetyouabouttwocansoftuna金枪鱼butoneofredshellsmightgetenoughtunatofeedabigfamilyforalongtime.Justlikeaplacethatcreatescoinsthere'sonlyoneplaceontheislandwheretheshellswhicharepolishedandstrungtogethertoform3﹣foot﹣longropesaremade.TheredwhiteandblackshellsallcomefromLangaLangaLagoonwhereartificialislandswerebuiltbylocalstoescapefromthewarlongago.Oncetrappedontheseislandslocalsneededacurrencytouseamongthemselvesandsotheshellcurrencywasborn. Justlikecryptocurrenciestherearethosewhothinktheislandersaresmarttoinvestinthistypeofmoneywhichisreportedtohaveriseninvalueoverthelastthreedecades.Itmightseemstrangebutwhatisapileofdollars?It'sjustaspeciallyprintedpieceofpaperthatwe'veassignedvalueto﹣﹣andprobablylessdurable耐用overtimethanthoseshells. 1WhatdoestheauthorintendtotellusinParagraph1? A.Atrendofcurrency. B.People'sinterestinBitcoin. C.Banks'controlovercurrency. D.Aneffectofcryptocurrencies. 2TheunderlinedwordhoardinginParagraph3canbereplacedby. A.selling B.polishing C.collecting D.hiding 3Accordingtothispassagewhatdeterminesthevalueofshells? A.Theircolor. B.Theirshape. C.Theirsource D.Theirweight. 4Whatistheauthorsattitudetowardstheislanders'investinginshells? A.Doubtful. B.Objective. C.Uncaring. D.Approving.
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词符号∧并在其下面写出该加的词. 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的词. 注意1.每处错误及修改均仅限一词 2.只允许修改10处多者从第11处起不计分. LastnightourschoolorganizedanEnglishCorner.Iwenttherewithdozenofstudentsmostofthemwereseniors.AndtherewasalsonativeEnglishspeakerwhowasinvitedtocommunicatewithus.Hewasveryhumorousandeasy﹣goingbutlovedansweringquestionsraisebystudents.ItwasthefirsttimethatIhaveattendedanEnglishCorner.Ididn'taskforasinglequestionbecauseIwasreallynervousandpooratspokenEnglish.SoIjustlistenedtohertalkingwithotherstudents.IwasdeterminedtopracticingspeakingEnglishashardasIcouldhopingtocommunicatewithforeignersfluentinEnglishinthefuture.
Englishisnowthefirstlanguageofabout400millionpeoplethemotherlanguageof12countriesandtheofficiallanguageofone﹣fifthofthelandareaoftheworld1meansone2everysevenpeopleintheworldspeaksEnglish. Moreandmorepeoplehavefounditimportant3learnEnglishwellinrecentyears.InItalyforexampleEnglishisamustformanytechnicaljobs.InChinaEnglishisthe4importantforeignlanguagethatislearnedatschool. TheEnglishlanguagehasneverstoppedchanging.Italwaysborrowswordsandphrasesfromotherculturestoenlarge5itvocabulary.6actualmodemEnglishisquitedifferentfromwhat7usehundredsofyearsago. Englishissowidelyusedthatithasbecomethestandardlanguagefor8communicateinternationally.About75%oftheworld'smail9beinEnglish.About60%oftheworld'stelephonecallsaremadeinEnglishandabout60%oftheworld'sradioprogramsarebroadcastinEnglish.What'smoreoverhalfoftheworld'sbooksandmagazinesarewritteninEnglish.In10wordEnglishisnowtheworld'sfirstlanguage.
Nooneknowswhomadethefirsticecream.SomepeoplethinkthatwatericesandmilkicesmayhavebeenmadebytheChinesebetweenthreethousandandathousandyearsago.InthattimethedishreachedIndia.TheIndiansinturnmanyhavepassedonthesecrettotheArabsandPersians. MarcoPoloanItalianwhotravelledwidelyinthethirteenthcenturynotedthathefoundtheChinesehadlongbeenmakingicesoutoffruitjuicesandmilk.FromthefourteenthcenturyonicesbecamepopularfirstinVeniceandthenthroughoutItaly. In1535whenCatherinedeMedeicisleftItalytomarrythefutureKingHerryIIofFranceshetookhercookswithher.TheymadedessertstheFrenchhadnevertastedbeforewhichwasicecream. AtfirsticecreamwasaluxuryinFrance.Onlyrichpeoplehadthemoneytobuyit.Thenin1660ayoungmanfromSicilyFranciscoProcopioarrivedinParis.Heopenedashopthatsoldicecreamatpricespeoplecouldafford.Thenhisicecreambecamesopopularthatothershopswereopened. About1640KingCharlesintroducedicecreamtoEnglandandsoonicecreamquicklybecamepopularinEnglandtoo. 1IcecreamwasunknowninFranceuntil. A.1660 B.1535 C.1774 D.1640 2WhointroducedicecreamtoEngland? A.KingCharles B.CatherinedeMedeicis C.FranciscoProcopio D.MarcoPolo 3Whatwillbeprobablytalkedaboutinthenextparagraphs? A.MarcoPolo'stravelintheworld B.Developmentoficecreaminothercountries C.DevelopmentoficecreaminEngland D.DevelopmentoficecreaminFrance 4What'sthispassagemainlyabout? A.MarcoPolo'stravel B.oneofChineseinventions C.Catherine'smarriage D.thehistoryoficecream
等比数列{an}中若a1＝1a5＝16则a2•a3•a4＝
现有两个小麦品种一个纯种小麦性状是高杆D抗锈病T另一个纯种小麦的性状是矮杆d易染锈病t．两对基因独立遗传．育种专家提出了如图所示的ⅠⅡ两种育种方法以获得小麦新品种．问 1方法Ⅰ与方法Ⅱ相比前者的优势在于． 2图中①和④基因组成分别为和． 3三过程采用的方法称为四过程最常用的化学药剂是五过程产生的抗倒伏抗锈病植株中的纯合体占．
已知函数fx＝x2+x+6存在x∈[02]使得fx≥a2﹣a成立则实数a的取值范围
在△ABC中角ABC所对的边的长分别为abc若asinA+bsinB＜csinC则△ABC的形状是
WhenAmericansKayandLarryDayfoundastoresellingkitesnearly20yearsagotheydecidedtobuyafewkitesfortheirfamily.ForfunLarryboughtoneforhimself.HewentoutandflewitanddecidedtogobackandaddmorefuntotheeventKayremembered. Sincethensheandherhusbandhavelovedkiteflying.Theyownmanykitesandplantripsaroundflyingthem.Theyalsoorganizeakite﹣flyingeventeachwinterintheirhometowninIowa.I'matpeacewhenI'mflyingakitesaidLarry. Kite﹣flyinghasalonghistoryasanactivityforadultsandchildren.Thecustomofflyingapieceofclothhighintheskybeganmorethan2000yearsagoinChina.Sincethenkiteshavebeenusedtodoscientificexperimentspowerboatstakepicturesfromtheairandmuchmore. Sometimesthebestflyingconditionshappeninwinter﹣onafrozenlakesaidKayDaywhowithherhusbandorganizestheColortheWindKiteFestival.IttakesplaceeveryFebruaryonClearLakeinIowa.Thefestivaladdscolortothewinterskyandgivespeopleareasontogooutsidesheadded.TheDaysinviteexpertflierstocomeandsharetheirloveforkiteswithlocalsandvisitors.Thisyearmorethan100childrenattendedakite﹣makingclass.Kitersareareallygoodgroupofpeople.It'safamilysaidLarry. Kaysaysthattheloveforkitescanspreadtootherseasily.ShesayshertwochildrenDylanandCardinstartedflyingkitesaboutthreeyearsagoafterattendingakitefestivaltheyheld.Theylikewatchingtheirparentsflykiteshappilytogether.Thesceneencouragesthemtoflykitesthemselves.IdoenjoyattendingkitefestivalsDylansaid.The13﹣year﹣oldboyenjoysitwhenhiskitemovesfreelythroughthesky. 1WhenLarryflewakite20yearsagohedecidedto. A.spreadhisloveforkitestohisfamily B.plantripstoflykites C.makekiteflyingmoreenjoyable D.holdakitefestival 2Whatdoesparagraph3mainlytalkabout? A.Kite﹣flyingactivitiesforkitelovers. B.Thehistoryofkites. C.Methodsofmakingakite. D.Theusageofkites. 3FromLarry'spointofviewthekitefestivalcan. A.attractmanyexpertsfliers B.maketheirhometownfamous C.bringpeoplemuchfreedom D.strengthenhumanrelations 4Whatcanbeinferredfromthelastparagraph? A.Childrenaregoodatflyingkites. B.Peopleofallagesloveflyingkites. C.Parents'interestscaninfluencetheirkids. D.Parents'skillsshouldbepassedontokids.
已知函数fx＝ab∈R． 1若关于x的不等式2ax﹣b＞0的解集为求fx＜0解集 2若a＝解不等式fx＞0的解集．
已知m∈R直线lmx﹣2+2y＝0恒过定点P则P的坐标为．
已知等比数列{an}__比q＝2a4是a3+2a5﹣6的等差中项． 1求数列{an}的通项公式 2求数列{an}的前n项和Sn．
文中共有10处语言错误每句中最多有两处.每处错误仅涉及一个单词的增加删除或修改. 增加在缺词处加一个漏词符号/\并在该句下面写出该加的词. 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. Wheneverthereisanexamaroundthecornerit'snormaltofeelanxiously.Naturallyyouarelikelytobeinyourroomstudyashardasyoucanbeforethebigday.Asthematteroffactthecolorofyourroomcouldhaveaninfluenceontheresultofyourexam.Ithasfoundthatpalecolorslikeblueorlightgreenmakepeoplerelaxingandcalm.Asaresultourbraingetslazyandinactivebutbecomeslessopentotakinginalargeamountofinformations.Onthecontrarybrightcolorscanhelpusconcentrateonataskeasilyandsolveproblemsefficiently.That'sbecausetheymayrelieveourstressbycheeringthemup.Sonexttimeyouhadtodealwithadifficulttaskmakesureofyouchoosearoomwithabrightcolor.
PoliceForcepresentsCommunityRoadshow2019 Wanttofindoutmoreaboutpolicework?ComeandvisitusatthevariouslocationsacrossSingapore.EnjoytheperformancesbythefriendlydogsfromthePoliceK9UnitandthePoliceBand. Comewithyourfamilyandtakepartinthefunactivities. OrganizedbytheSingaporePoliceForce 1WhatshalleachparticipantgetinCommunityRoadshow2019? A.Afunpack. B.Someprize. C.SomeVoucher. D.BouncyCastle. 2HowshouldapersonsignupforArtCompetition? A.Onsite. B.Byemail. C.Byphone. D.ThroughtheInternet. 3Whichofthefollowingorganizedtheactivity? A.SerangoonCentre. B.RockClimbCompany. C.SingaporePoliceForce. D.PoliceortCompany.
WhenIwasfifteenyearsoldItoldmymotherIwantedcontactlenses隐形眼镜.Somegirlsatmyschoolhadgotthemandtheylooked1withouttheirglasses.MomtoldmethatIwouldhavetogetan2topayforthelensesmyself.When3herthatthelegalworkingagewassixteenshesaidthatshewouldaskherformer4ofagrocerystoretohiremeparttime.Shesaidthatshewasgreatly5andencouragedbyhimwhensheworkedthere. Ihad6earnedmoneybybabysittingrunningerrandsandshovelingsnow.Sothiswasmyfirstexperienceofworkingwithadults.OnmyfirstdayI7groceries.Everyitemhadtobeplacedtidilyinbrownpaperbags.EventuallyIwasgiventhe8ofrunningthesnackbar.Mydutymainly9makinghotdogsofferingsupplieslikefreshdonutsandpastriesand10customers.AsittookaboutanhourforthehotdoggrilltocooldownafterIshutitoffIwasusually11employeetoleavethestore.Iwasvery12incheckingmyworkareatoensurethat13wascleanandtheelectronicswere14beforeIwenthome.IlovedmyworktheresoI15workingatthegrocerystorethroughouthighschool. Thisexperiencefinallynotonlyhelpedmegetmycontactlensesbutalso16memanythings.Workingwithadultsgavemean17oftheirdailystrugglesandthe18ofbeingawifeandmotherwhileworkingfulltime.WhenIwasatworkIwas19likeanadultsoIhadtoworkhardformypaycheck.NowwhenIgoshoppingatgrocerystoresIespecially20theemployeesthere. 1A.morespecial B.moreintelligent C.prettier D.brighter 2A.chance B.approval C.plan D.job 3A.reminded B.persuaded C.warned D.reported 4A.student B.colleague C.boss D.relative 5A.blamed B.educated C.moved D.supported 6A.mainly B.previously C.fairly D.exactly 7A.checked B.counted C.bagged D.purchased 8A.present B.reward C.benefit D.responsibility 9A.deserved B.occupied C.involved D.devoted 10A.serving B.controlling C.finding D.pleasing 11A.last B.best C.first D.fastest 12A.strong B.nervous C.excited D.careful 13A.anything B.something C.everything D.nothing 14A.turneddown B.turnedoff C.turnedin D.turnedaway 15A.kept B.suggested C.practiced D.considered 16A.taught B.lent C.showed D.saved 17A.detail B.understanding C.method D.goal 18A.cost B.meaning C.happiness D.challenge 19A.hired B.treated C.encouraged D.punished 20A.respect B.praise C.envy D.impress
Switchingfromchildhoodtoadulthoodcanbechallenging.1Workonnotactinglikeachildbymanagingyouremotions.Withalitebitofpracticeyouwillbegintoseeyourselfactingmorelikeanadultthanachild ●Acceptresponsibilityforyouractions. Youshouldtakeresponsibilityforyouractionswhethertheyareintentional故意的orunintentional.2Failingtoacceptresponsibilitymayseemlikeagoodideaatthetimebutinthelongtermitwillnotbenefityou.Forexampleifyouaccidentallybackintoyourneighbor'scarletthemknowbywritingthemanoteorknockingontheirdoor.Thencorrectyourmistakebypayingforthedamage. ●Showpeoplerespect. Respectyourpartnerfamilymembersfriendsandstrangers.3Asyougrowupandmatureyoushouldunderstandtheconceptofrespectandwhyitisimportant.Givingrespectwillalsogiveyoumorerespectinreturn. ●Developawaytohandleconflictmaturely. Whenyouarefacedwithaconflictitisimportanttokeepyouremotionsincheck.Controlyourangerandavoidbecomingaggressive.4Giveyourselftimetocooldownifyouarerallyangry.Thiswillpreventyoufromsayinganddoingthingsthatyoushouldn'tdointheheatofthemoment. ●Receivefeedback反馈positively. Peoplelearnandgrowbyreceivingfeedbackandcriticismfromothers.Youshouldacceptthatyoudon'tknoweverythingandthatfeedbackfromanexpertisnotmeanttohurtyou.Itismeanttohelpyou.Forexamplethoroughlyreadthroughyoureditsonyourresearchpaper.5. A.Takeonadultresponsibilities. B.Oftentimesyoumaystillfeellikeachild. C.Childrenareoftenselfishanddisrespectful. D.Itisasignofmaturityandrespectforothers E.Theseeditswillhelpimproveyourwritinginthefuture. E.Thiscanhelpyougethighermarksinmanyofyoursubjects. G.Takeadeepbreathlistenandworkthroughtheconflictwiththeotherindividual.
Whenscholarsofinternationalrelationspredictthatthe21﹩tcenturywillbeaChinesecenturytheyarefullofreasons.1AmericaremainstheonlysuperpowerChinaisresponsibleforanimportantshareofglobalchange.Since2startofthefinancialcrisisin＝2008forexampleChinahasaccounted345%ofthegaininworldGDP.In1990about＝750millionChinesepeoplelivedinextremepovertytodayfewerthan10milliondo.ItsGDPperpersonintermsofpurchasing﹣power4risetentimessince1990. China'samazing5performhasgreatlyaffectedtheworld'seconomicoutput.TheEconomisthasworkedoutageographiccenteroftheglobaleconomyby6takeanaverageofeachcountry'slatitudeandlongitude经纬度7measurebyitsGDP.AttheheightofAmerica'scontrolthispoint8previoussatinthenorthAtlantic.ButChinahaspulleditsofareast9theglobalcenterofeconomicgravity10benowinSiberia.
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