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若空间两条直线a和b没有公共点,则a与b的位置关系是( )
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若空间中有两条直线则这两条直线为异面直线是这两条直线没有公共点的
充分非必要条件
必要非充分条件
充分必要条件
既非充分又非必要条件
下列描述不能够确定空间平面位置的是
不在同一直线上的三个点
一条直线和直线外一点
两条相交直线
两条交叉直线
若空间中有两条直线则这两条直线为异面直线是这两条直线没有公共点的
充分不必要条件
必要不充分条件
充要条件
既不充分也不必要条件
若空间有两条直线则这两条直线为异面直线是这两条直线没有公共点的的
充分非必要条件
必要非充分条件
充要条件
非充分非必要条件
下列四个结论⑴两条不同的直线都和同一个平面平行则这两条直线平行.⑵两条不同的直线没有公共点则这两条直
如果两条直线a和b没有公共点那么a与b的位置关系是.
在空间中①若四点不共面则这四点中任何三点都不共线②若两条直线没有公共点则这两条直线是异面直线.以上两
两条异面直线是指
空间中两条没有公共点的直线
平面内一条直线与该平面外的一条直线
分别在两个平面内的直线
不同在任何一个平面内的两条直线
若空间中有两条直线则这两条直线为异面直线''是这两条直线没有公共点的
充分非必要条件
必要非充分条件
充分必要条件
既非充分又非必要条件
在一个圆中给出下列命题其中正确的是
若圆心到两条直线的距离都等于圆的半径,则这两条直线不可能垂直.
若圆心到两条直线的距离都小于圆的半径,则这两条直线与圆一定有四个公共点.
若两条弦所在直线平行,则这两条弦之间的距离一定小于圆的直径.
若两条弦所在直线不平行,则这两条弦一定在圆内有公共点.
在同一平面内若两条直线相交则公共点的个数是________;若两条直线平行则公共点的个数是___
下列四个结论⑴两条直线都和同一个平面平行则这两条直线平行⑵两条直线没有公共点则这两条直线平行⑶两条直
0
1
2
3
空间中两条直线若没有交点则这两条直线的位置关系是
相交
平行
异面
平行或异面
在一个圆中给出下列命题其中正确的是
若圆心到两条直线的距离都等于圆的半径,则这两条直线不可能垂直
若圆心到两条直线的距离都小于圆的半径,则这两条直线与圆一定有4个公共点
若两条弦所在直线不平行,则这两条弦可能在圆内有公共点
若两条弦平行,则这两条弦之间的距离一定小于圆的半径
下列四个结论⑴两条直线都和同一个平面平行则这两条直线平行⑵两条直线没有公共点则这两条直线平行⑶两条直
0
1
2
3
3.00分如果两条直线a和b没有公共点那么a与b的位置关系是.
两条平行直线和圆的位置关系定义为若两条平行直线和圆有四个不同的公共点则称两条平行线和圆相交若两平行直
或
或
或
或
在空间中①若四点不共面则这四点中任何三点都不共线②若两条直线没有公共点则这两条直线是异面直线.以上两
分别在两个平面内的两条直线的位置关系是________不平行的两条直线的位置关系是________两
若空间两条直线ab没有公共点则其位置关系是____________.
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下列有机物系统命名正确的是
如图反比例函数y=x>0的图象经过矩形OABC对角线的交点M分别交ABBC于点DE.若四边形ODBE的面积为12则k的值为.
如图在菱形ABCD中已知AB=4∠ABC=60°∠EAF=60°点E在CB的延长线上点F在DC的延长线上有下列结论①BE=CF②∠EAB=∠CEF③△ABE∽△EFC④若∠BAE=15°则点F到BC的距离为2﹣2.则其中正确结论的个数是
10分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:在缺词处加一个漏字符号∧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. WhennewscamethatIwasnotchosenasthememberofthevolleyballteamIwassuchfrustratedthatIalmostdecidedtogiveup.HowevermybestfriendMirandaanalyzedmyproblemspointedoutthatmylazinessandpoorpreparationledmyfailure.FromthenonIdevotedallmysparetimetopracticeplayingandconsultinghisteachersaboutskillseveryday.WhenanotherchancecameIhadgotfullyprepared.AsaresultofIwasselectedandbecameoneofthemostimportantplayerinourschoolteam.FromthisstoryIamdefiniteconvincedthatthebetterpreparedwearethemuchlikelyweareabletoachieveourgoals.
如图⊙O的直径AB垂直于弦CD垂足是点E∠CAO=22.5°OC=6则CD的长为
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10分 Flavoring Mostdrinksstatingthattheyarefruit﹣flavored水果味道的containnofruitatallwhilemostoftherestcontainonlyasmallquantityoffruitaccordingtoastudycarriedbytheBritishFoodCommission. Shoppersneedtocheckthelabels标签beforebuyingdrinksthoughsometimestheactualcontentcanbenon﹣existentsaidFoodCommissionspokespersonIanTokelove.Foodproductionishighlycompetitive.1Itwillincreaseprofitsandconsumerswon'talwaysrealizetheyarebeingtricked. Flavoringsarefocusedontheflavorsofnaturalfoodproductssuchasfruitsmeatsandvegetablesorcreatingflavorforfoodproductsthatdonothavethedesiredflavors.Researchersanalyzedthecontentsof28strawberry﹣flavoredproductssoldinstores.2Ofthe11productsthatdidcontainstrawberriesfiveofthemcontainedlessthanonepercentrealfruit.Inadditioneachjuiceboxcontainednearlyeightteaspoonsofsugar. 3Let'stakejamasanexample.Somestrawberry﹣flavoredjamwaslabeledascontainingnoartificialcolorsflavorsorsweetenersbutitcontainedabsolutelynostrawberriesatall. 4Consumershavetherightstoknowclearlyaboutwhattheyhavebought.UndercurrentUKlawfoodpackagesdonothavetodistinguishbetweennaturalandartificialflavoring.Describingaproductasstrawberryflavorandcoveringthesurfaceofthepacketwithpicturesofstrawberriesismisleading.5UnfortunatelyitisalsolegalandwidespreadTokelovesaid.It'stimetotakemeasurestoprotecttheconsumers'rights. A.Theproductswhichcontainrealfruitarepopularwithpeople. B.Evenproductsadvertisedasmorenaturaloftencontainednofruit. C.Theyfoundthatabout60vpercentofthemdidn'tcontainanyfruitatall. D.Ifcompaniescancuttheircostsbyusingflavoringtheyarelikelytodoso. E.Itisimportantandneessarytodemandasmallamountofflavoringintheproducts. F.Actuallytheproductcontainsjustatinypercentageofstrawberryorevennofruitatall. G.TheFoodCommissionsuggestedallflavorsusedinaproductshouldbelistedonthepackaging. 1. 2. 3. 4. 5.
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30分AtfirstpeopleintheUSthoughtEbola埃博拉wasonlyadiseaseaccompaniedwithfeverandfoundinAfricaatthebeginning.1thenamanfromwestAfricadiedfromEbolaatahospitalinDallasTexas.Andtwonurses2forhimbecameinfected感染withtheviruswhichmadetheUSgovernmentpublishnewguidelinesto3healthworkers. TopAmerican4haverepeatedlysaidthatmostpeoplehavelittlechanceofbeinginfected.Expertshave5thatEbolacanonlybespreadthroughinfectedperson'sbodyfluids﹣likeblood.Butit6thatmanyAmericansare7whattheyhaveheard. Arecentsurveyfoundmorethan80percentofAmericansbelievethatEbolacanbespreadinmany8includingairforcedthroughthenoseormouth.BesidestheHarvardSchoolofPublicHealth9thefindings.Thestudyalsoshowedthatmostadultsfeartherewillbean10ofEbolaintheUnitedStatessoon.11surveyfoundthatmorethan70percentofAmericanswouldsupportcallsto12traveltoandfromEbola﹣affectedpartsofAfrica. ThomasFriedenheadstheU.S.CentersforDiseaseControlandPrevention.Whenaskedwhether 13officialshadconsideredatravelbanMr.Friedenhad14tosay:Wewon'tbeabletochecktravelersfor15whentheyleaveorwhentheyarrive.Wewon'tbeableaswedo16totakeadetailedhistorytoseeiftheywere17whentheyarrive.Whenthey18wewouldn'tbeabletoimposequarantine强加隔离aswenowcaniftheyhavehigh﹣risktouch. LastweekPresidentBarackObamaurgedAmericansnotto19whathecalledpanicorfear.ThisweektheadministrationannouncedthatalltravelersreachingtheUnitedStatesfromsomeAfricannationsare20topassthroughoneoffiveairports. 1.A.Just B.Yet C.So D.Even 2.A.arranging B.caring C.searching D.standing 3.A.treat B.attend C.inspec tD.protect 4.A.policemen B.officers C.physicists D.doctors 5.A.stated B.suggested C.considered D.regretted 6.A.proves B.happens C.says D.appears 7.A.studying B.discussing C.questioning D.determining 8.A.ways B.areas C.organs D.countries 9.A.announced B.received C.realized D.rejected 10.A.increase B.income C.decrease D.outbreak 11.A.Theother B.Another C.Thesame D.One 12.A.forbid B.expect C.require D.allow 13.A.foreign B.royal C.African D.federal 14.A.that B.this C.nothing D.those 15.A.change B.money C.fever D.crime 16.A.immediately B.previously C.presently D.regularly 17.A.examined B.searched C.explored D.exposed 18.A.leave B.arrive C.live D.stay 19.A.lookforwardto B.payattentionto C.giveinto D.addupto 20.A.persuaded B.required C.advised D.guided
在我市“青山绿水”行动中某社区计划对面积为3600m2的区域进行绿化经投标由甲乙两个工程队来完成.已知甲队每天能完成绿化的面积是乙队每天能完成绿化面积的2倍如果两队各自独立完成面积为600m2区域的绿化时甲队比乙队少用6天. 1求甲乙两工程队每天各能完成多少面积的绿化 2若甲队每天绿化费用是1.2万元乙队每天绿化费用为0.5万元社区要使这次绿化的总费用不超过40万元则至少应安排乙工程队绿化多少天
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如图在岷江的右岸边有一高楼AB左岸边有一坡度i=12的山坡CF点C与点B在同一水平面上CF与AB在同一平面内.某数学兴趣小组为了测量楼AB的高度在坡底C处测得楼顶A的仰角为45°然后沿坡面CF上行了20米到达点D处此时在D处测得楼顶A的仰角为30°求楼AB的高度.
8分Aslifeexpectancyincreasesnowadaystheaveragepersonliveswellbeyondtheageofretirement.Asaresulttheelderlymakeupanever﹣increasingpercentageofsocietywhichmakesitmoreimportantthaneverforarealefforttobemadeinimprovingthelivesofseniorcitizens. Onewaytodealwiththesituationwouldbetoensurethattheelderlyhaveenoughmoneyonwhichtolive.Obviouslywhenapersonstopsworkingtheystillrequireasourceofincometocovertheirbasicneedssuchasfoodaccommodationandheating.Aclearsolutiontotheproblemisforthegovernmenttomakesurethatthestatepensionisadequatefortheseneeds. Stepsshouldalsobetakentoovercomethehealthproblemstheelderlyface.Thegovernmentshouldalsoprovideaccesstothebesthealthcareavailablewhichmaynecessitatepayingforresidentialhomeswheretheelderlycanhaveround﹣the﹣clocknursingorattheveryleastprovidingmedicationfreeofchargetoallpeopleoveracertainage. Thelivesofoldpeoplecouldbeimprovedifattemptsweremadetoaddresstheproblemofsocialisolation.Ifweorganisedtripsfortheelderlytocommunitycentresvisitsfromsocialworkerstheirproblemoflonelinesscanbereducedalotwhichmarksthelivesofsomanyoldpeoplelivingaloneandfarfromtheirfamilies. Onefinalsuggestionwhichwouldhelpenormouslyistochangetheattitudeofthecommunitytowardsitsoldermemberswhoarealltoooftenseenasaburdenonsocietyanddismissedashavinglittletodowithmodernlife.Weneedtobetaughtfromanearlyagetorespecttheviewsofoldpeopleandappreciatetheirbroaderexperienceoflife.Thiswouldhelpsocietyasawholeandencourageappreciationoftherolethatoldpeoplecanstillplaytoday. 1.Whatdoesthepassagemainlytalkabout? A.Alltheelderlycanenjoyfreemedication. B.Thenursescantakegoodcareoftheelderly. C.Somesuggestionswouldbemadetoimprovethelivesoftheelderly. D.Thehealthcareavailabletotheelderlyisgood. 2.TheunderlinedwordaddressinParagraph4probablymeans. A.findout B.dealwith C.putdown D.pickup 3.Whatfactorsaffectedtheoldpeople'slife? a.thestatepension b.thebasicneeds c.theattitudeofthecommunity d.theexperienceoflife e.socialisolation f.medicalcare A.abcd B.bcde C.cdef D.acef 4.Accordingtothelastsuggestiontheoldpeople. A.shouldberespectedbyallofus B.havetogathermorelifeexperience C.mayberegardedasourheavyburden D.mustchangetheirattitudetothecommunity
6分EachmorningGrandpawasupearlysittingatthekitchentablereadinghisbook.Hisgrandsonwantedtobejustlikehimandtriedtocopyhimineverywayhecould.OnedaythegrandsonaskedGrandpaItrytoreadthebookjustlikeyoubutIdon'tunderstanditandIforgetwhatIunderstandassoonasIclosethebook.Whatgooddoesreadingthebookdo? ThegrandpaquietlyturnedfromputtingcoalinthestoveandrepliedTakethiscoalbasketdowntotheriverandbringmebackabasketofwater.Theboydidashewastoldbutallthewaterleakedoutbeforehegotbacktothehouse.ThegrandpalaughedandsaidYou'llhavetomovealittlefasternexttimeandsenthimbacktotheriverwiththebaskettotryagain. Thistimetheboyranfasterbutagainthebasketwasemptybeforehereturned.Outofbreathhetoldhisgrandpathatitwasimpossibletocarrywaterinabasketsohewenttogetabucketinstead.ThegrandpasaidIdon'twantabucketofwater;Iwantabasketofwater.You'rejustnottryinghardenough. Theboyagaindippedthebasketintotheriverandranhardbutwhenhereachedhisgrandpathebasketwasemptyagain.OutofbreathhesaidGrandpait'suseless!Soyouthinkitisuseless?thegrandpasaidLookatthebasket. Theboylookedatthebasketandforthefirsttimeherealizedthatthebasketwasdifferent.Ithadbeentransformedfromadirtyoldcoalbasketandwasnowclean.Grandsonthat'swhathappenswhenyoureadthebook.Youmightnotunderstandorremembereverythingbutwhenyoureadityou'llbechangedinsideandout. 1.Whatpuzzledthegrandsonmostwas. A.whetheritwasusefultoreadbooks B.whyheforgotwhathereadsoon C.whatkindofbookhecouldunderstand D.howhecouldreadbookslikehisgrandpa 2.WhydidGrandpaaskhisgrandsontofetchabasketofwater? A.Totrainhimtorunfaster. B.Tocleanthedirtybasketintheriver. C.Topunishhimfornotreadingcarefully. D.Togethimtorealizetheuseofreadingbooks. 3.Whatlessoncanwelearnfromthestory? A.Theoldarealwayswiserthantheyoung. B.Itisfoolishtocarrywaterwithabasket. C.Readingbookscanchangeapersongradually. D.Youcan'texpecttorememberwhateveryouread.
PM2.5是指大气中直径小于或等于2.5微米的颗粒物也叫可入肺颗粒物与肺癌哮喘等疾病的发生密切相关是灰霾天气的主要原因.它主要来自化石燃料的燃烧如机动车尾气燃煤等.下列与PM2.5相关的说法不正确的是
10分Justlikechildrenbabyanimalsspendcountlesshoursatplay.Afterstudyinganimalplayformanyyearsscientistsrecognizethatyounganimalplayispracticeforadultbehavior.Todaythisplayisroughlydividedintothefollowinggroups. Locomotorplayreferstothemovementsanimalscarryoutintheirplay.Runningleapingturningandkickingaresomeofthemostcommonexamplesoflocomotorplay.Anadultdeermayrunleapandtwisttoescapeitsattackers.Playmovementslikethesesurelymakeyounganimalsnimble.Somedaytheseskillsmighthelpsavetheirlives. Movingforwardslowlyattackingsuddenlyandbitingareexamplesofpredatoryplaythathelpyoungpredatorsprepareforalifeofrunningafterandtakingholdofotheranimals.Wildcatswolvesandbearsarepredators.Itisverycommontoseetheseyounganimalsplaythiskindofgameswhichsharpentheirskillsandteachthemabouttheirstrengthsandlimitations. Forchildrenplayingwithtoysisbothfunandeducational.Ithelpsimprovetheirhandandeyemovementsaswellasdevelophandskillstoaccomplishtasks.Itisthesamewithanimals.Youngchimpanzeesimprovetheirhandskillswhileplayingwithsticks.Birdsalsoplaywiththingsinwaysthatteach.Swallowsdropandrecoverfeathersinmidair.Divingsuddenlytocatchthefeathersisagoodpracticeforcatchingflyinginsects. Socialplayhelpsanimalslearnhowtobehavewhentheyrunintootheranimals.Anditteachesanimalsaboutcommunication.Ananimalgivessignalstoletanotheranimalknowitwantstoplay.Manyanimalsgivesignalsbyshowingaplayface.Insomewaysthisfaceislikeahumansmile;theanimalholdsitsmouthinarelaxedandopenmanner.Duringplay﹣fightssomeanimalsmaystepbackwardstosignalthattheyareplayingandnotactingseriously. Untilnowscientistshaveunderstoodplayfulactshelpprepareanimalsfortheirseriousadultsituations.Butthenumbersofplayfulspeciesandexamplesofanimalplayarevast.Thepurposeofanimalplaymayhavemeaningsscientistshavenotdiscoveredyet. 1.Themainpurposeofthetextisto. A.askustotakegoodcareofwildanimals B.encourageustolearnmoreaboutanimals C.entertainuswithinterestinganimalstories D.showussomethingaboutanimalbehavior 2.TheunderlinedwordnimbleinParagraph2canbestbereplacedby. A.cruel B.swift C.curious D.strong 3.Whichofthefollowingbelongstopredatoryplay? A.Adeerrunsleapsandturns. B.Achimpanzeeplayswithastick. C.Alionmovesslowlyandmakesanattacksuddenly. D.Adogholdsitsmouthinarelaxedandopenmanner. 4.BasedonParagraph5aplayfaceis. A.atypeofsignalbetweenanimals B.anameforakindofanimalplay C.anactivitythatinvolvesadultanimals D.anactionthatistaughttoanotheranimal 5.Whichofthefollowingshowsthestructureofthetext?
下列运算正确的是
15分Agroupoffrogsweretravelingthroughthewoodsandtwoofthem1fallintoahole.Alltheotherfrogslookeddown.Whentheysawhowdeep2holewastheytoldthetwofrogsthattheywoulddiesoon. Atfirstbothofthetwofrogsdidn'tcaretheirwordsandtried3besttojumpoutofthehole.Theotherfrogskepttellingthemtostopbecausetheythoughttherewasnochance4jumpoutofsuchadeephole.Finallyoneofthetwofrogsbelievedthesewordsandgaveup.Hefelldownanddied. Theotherfrogcontinuedtojumpashardashecould.Onceagainthecrowdoffrogsshoutedathimtostopthepainandjustdie.Hejumpedeven5hardandfinallysucceeded.WhenhegotouttheotherfrogsaskedDidn'tyouhearus?6theirgreatsurprisethefrogturnedouttobedeaf.Hethoughttheywerehelpinghimallthetimenot7stophim. Thisstoryteachestwolessons:Thereispoweroflifeanddeathinthetongue.Well﹣meantwordscanhelppeopleintrouble.Butevilwordssometimescankillthem.Becarefulof8yousay. Rememberthepowerofwords.Anyonecanspeakwords9arelikelytomakepeoplegiveupindifficult10time. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10.
6分Noonewouldmuchliketheideaofeating61poundsoftomatoesaday.Butiftheirgoodnesswasputintoaneasy﹣to﹣swallowpillthatyouweretoldmightpreventstrokes中风andheartattacksyouwouldprobablybeputtinginanordertomorrow. Researchersbelievetheymayhavecomeupwithjustthataftertrials.Thedailypillcontainsachemicalcalledlycopenewhichmakestomatoesredandisknowntobreakdownfatinthevessels血管.ACambridgeUniversitystudyfoundtakingthepillsimprovedbloodflowandtheliningofvesselsinpatientswithpre﹣existingheartconditions.Italsoincreasedtheflexibilityoftheirvesselsby50percent.Thescientistsbelieveitcouldlimitthedamagecausedbyheartdisease﹣responsiblefor180000deathsayear﹣andhelpcutthe49000deathsayearfromstrokes.Theyalsohopeitcouldbenefitthosewitharthritis关节炎diabetes糖尿病andevenslowtheprogressofcancer. Eachpillisequaltoeatingaround61poundsofripetomatoes.StudieshaveshowneatingaMediterranean﹣styledietrichintomatoesfishvegetablesnutsandoliveoilcansignificantlyreducecholesterol胆固醇andhelppreventcardiovasculardisease. Preliminaryresultsfromatwo﹣monthtrialinwhichthepillwasgivento36heartdiseasepatientsand36healthyvolunteerswithanaverageageof67werepresentedatameetingoftheAmericanHeartAssociation.Itwasshowntoimprovethefunctionoftheendothelium﹣thelayerofcellsliningbloodvessels.Italsoimprovedtheirsensitivitytonitricoxidethegaswhichcausestheenlargementofthevesselsinresponsetoexercise. IanWilkinsonheadofCambridgeUniversity'sclinicaltrialsunitsaidTheseresultsarepotentiallyverysignificantanditmeetsthegoalbutweneedmoretrialstoseeiftheytranslateintofewerheartattacksandstrokes. Furtherstudiesareplannedwithresearchershopingitcouldofferachoiceforheartdiseasesuffererswhocannottakethecholesterol﹣lowingdrugs. MikeKnaptonheadoftheBritishHeartFoundationsaidAlthoughthisshowedlycopeneimprovedbloodflowinpeoplewithheartdiseasethat'salongwayfromdemonstratingthattakingitcouldimproveoutcomesforpeoplewithheartdisease.Thebestwaytogetthebenefitsofagooddietistoeatplentyoffreshfruitandvegetables. 1.WhatcanweinferfromParagraph1? A.Wecaneattoomuchtomatofood. B.Tomatoesarehelpfultostrokesandheartattacks. C.Tomatoeswilllosehealthyelementswereputintopills. D.Wehadbetternoteattomatoes. 2.Wecanlearnfromthepassagethatthepills. A.areattheexperimentstage B.cancureallthedisease C.arewidelyusedamongpatients D.costpatientssolittlemoney 3.WhatWasIanWilkinson'sopiniononthetrial? A.Disappointing. B.Surprising. C.Satisfactory. D.Terrible.
下列关于合成材料的说法中不正确的是
6分NingZetaohasbecomeChina'snewswimmingstarduetohisamazingperformanceatthe2014AsianGamesinIncheon仁川SouthKorea.Withalreadytwogoldmedalsinhandthe21﹣year﹣oldclocked47.70secondsinthe100mfreestylesettinganewAsianrecord.ThisresulthasbeenrecognizedbyFINAastheworld'sthirdbesttimethisyearfastenoughtohavewonagoldmedalinlastyear'sBarcelonaWorldChampionships.ItismyfirstinternationaleventsaidNingwholaterwonafourthgoldmedalinIncheon.Iamhappythatmyresultsareprettyclosetomypersonalbest. BorninthecentralChinesecityofZhengzhouNingenteredthelocalteamattheageof11andjoinedthenavyteamin2007.Hefirstcaughtpeople'sattentionin2009whenhefinishedeighthinthe200mindividualmedley混合泳attheNationalGames. NeverthelessNingsufferedfromboneinfectioninbothkneesforalongtimewhichmadehimunabletotrainhardonhiskicks.Healsohadanindigestionproblemandhadtoeatsoftfoodwhichiseasytodigest.Hispoorstomachevenmadeitimpossibleforhimtocompleteweek﹣longfulltimetraining.Buttheyoungswimmernevergivesup.HisidolisthegreatRussianswimmerAlexanderPopovwhocontinuedtowinOlympicgoldmedalsafterhewasstabbed刺伤onastreet.NingsaidHewasarealfighterandIneedtolearnfromhim. TakenbettercareofbycoachesanddoctorsNingcannowtrainasnormallyasothers.Andthatiswhyhecangettoday'sachievements.ThegoldmedalsattheAsianGamesalsoboostedtheconfidenceofthenewswimmingstarwhohopestoenterthenationalteamandcompeteforChinainmoreinternationalevents.Chinesemaleswimmershaveneverbeenplacedamongtopeightintheshort﹣distancefreestylehesaid.IhopeIcandoitjustlikewhatSunYangdidinthemid﹣longdistancefreestyle. 1.Thebesttitlecouldbe. A.NingZetaoaworldfamousswimmer B.NingZetaoapromisingrisingstar C.NingZetaoastrong﹣willedsoldier D.NingZetaoaworldgoldmedalist 2.Wecanlearnfromthepassagethat. A.theresultsNinggotinIncheonarehisbest B.Ningisgoodatboth100mand200mfreestyle C.NingbrokeanAsianrecordatthe2014AsianGames D.Ninghasalreadygot5goldmedalsintheinternationalevent 3.Itcanbeinferredfromthepassagethat. A.somehealthproblemshavelittleeffectonNing'straining B.beingwellcaredofisthemainreasonforNing'sachievements C.theChineseswimmershavenevergotintothetopeighthintheworldevent D.goldmedalistasNingisheisnotyetamemberofNationalSwimmingTeam
函数y=中自变量x的取值范围是
25分假定你是希望中学学生李华得知2017年香港大学要在大陆进行自主招生的消息后有意向香港大学申请参加自主招生考试请用英语写一封自荐信主要包括:1.个人信息2.性格爱好与特长3.学习情况注意:1.词数100左右;2.信的开头已为你写好不计入总词数;3.可根据内容要点适当增加细节以使行文连贯.4.参考词汇:自主招生independentrecruitmentDearSirMynameisLiHuafromHopeHighSchool.YoursLiHua.
某班七个兴趣小组人数如下566x789已知这组数据的平均数是7则这组数据的中位数是
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