在Rt△ABC中，∠A为直角，AC边所在直线的方程为x﹣2y﹣4＝0，点（﹣3，4）在直线AB上，斜边中点坐标为（2，0）． （1）求直线BC的方程； （2）设圆G为Rt△ABC的外接圆，若圆G上存在两点P、Q，使得P、Q关于y轴的对称点在直线ax+y+4＝0上，求a的取值范围．

某次探究加速度a跟物体所受合力F和质量m的关系实验过程是 ①图a所示为实验装置图．图b为某次实验得到的一段纸带计数点ABCDE间的时间间隔为0.1s根据纸带可求出小车的加速度大小为m/s2．结果保留两位有效数字 ②保持小车质量不变改变砂和砂桶质量进行多次测量．根据实验数据做出了加速度a随拉力F的变化图线如图c所示．图中直线没有通过原点其主要原因是． ③保持砂和砂桶质量不变改变小车中砝码质量进行多次测量得到小车加速度a质量m及其对应的的数据如表中所示 a．请在坐标纸中画出a﹣图线 b．根据作出的a﹣图象可以得到的结论是．

PartoneFirstMajorNovels IfDickenshadremainedtheauthorofPickwickOliverTwistandTheoldCuriosityShophemighthavegainedlastingfameonlyasanauthorofcheerfulcomedy.ButDombeyandSonpublishedin1846andcontinuedtill1848isarealisticnovelofhumanlifeinasocietywhichhadtakenmoreorlessitsmodernform.ThenovelisastudyoftheinfluenceofthevaluesofabusinesssocietyonthemembersoftheDombeyfamily. ParttwoDarknovels In1851Dickenswasstruckbythedeathofhisfatherandoneofhisdaughterswithin2weeks.Partlyinresponsetotheselosseshecreatedaseriesofworkswhichhavecometobecalledhisdarknovelsandwhichrankamongthegreatestsuccessoftheartoffiction. ParthreeLaterWorks In1859DickenspublishedATaleofTwoCitiesahistoricalnoveloftheFrenchRevolutionwhichisreadtodaymostoftenasaschooltext.Itisfinepictureofthehistoricalperiodandamovingtaleofasurprisinglymodernhero.BesidespublishingthisnovelinthelatelyfoundedAlltheYearRoundDickensalsopublished17articleswhichappearedtogetherwiththenovelasabooklater. Dickens'snextnovelGreatExpectations1860～1861tellsthestoryofayoungman'smoraldevelopmentinthecourseofhislife﹣fromchildhoodintheprovincestogentleman'sroleinLondon.NotbasedonhisownlifelikeDavidCopperfieldGreatExpectationsbelongstotypeoffictioncalledinGermanBildungsromanthenovelofaman'seducationorformationbyexperience. 1WhichofthefollowingDickens'novelshowsaclearchangeofstyle? A.DavidCopperfield B.Pickwick C.DombeyandSon D.OliverTwist 2AccordingtothepassageATaleofTwoCities. A.isabouttheIndustryRevolution B.canbefoundinmostofthetextbooks C.isbetterthanhisdarknovels D.isprobablypublishedinanewmagazine 3InGreatExpectationDickenswritesabout. A.thegrowthofaman B.howtobecomeagentleman C.hisownlifeexperience D.aman'sschooleducation

如图四边形ABCD是正方形连接AC将△ABC绕点A逆时针旋转α得△AEF连接CFO为CF的中点连接OEOD． 1如图1当α＝45°时请直接写出OE与OD的关系不用证明． 2如图2当45°＜α＜90°时1中的结论是否成立请说明理由． 3当α＝360°时若AB＝4请直接写出点O经过的路径长．

Aworkingpartyhasbeensetuptothecauseoftheaccident. A.lookover B.lookthrough  C.lookinto D.lookup

Brookewantedadollhouseandsomesugarcookies.Sothe6﹣year﹣oldaskedAlexatogetthem.Alexawasn'thermomorbabysitter.It wasavoice﹣activatedhomeassistantpoweredbyAI人工智能.AnditmadeBrooke'swishescometrue.Afewdayslatermuchtoherparents'surprisea﹩170dollhouseandfourpoundsofcookiesshowedup.Theyatethecookiesandgaveawaythedollhousetoalocalhospital.Andthat'snottheendofthestory.WhenanewsreportertoldthestoryofwhathappenedonTVAlexadevices设备inmanylisteners'homeswokeupandtriedtoorderdollhouses! Alexaisn'ttheonlyAIwillingtoserveyou.AppleHomePodhasSiriGoogleHomehasitsAssistantandtheupcomingGalaxyHomedevicewillhaveBixby.Peoplewho havethesedevicesusethemmainlyforlisteningtomusiccheckingtheweatherandsettingtimers.AccordingtoareportfromTheInformationnowadaysvoiceshoppingisrare.Butmanyscientistspredict aboom增长invoiceshoppinginthenearfuture.Isthatagoodthing? ▲.Youcanshoutoutanorderassoonasyouthinkofitevenifyouarecookingcleaningordriving.Inadditionpeoplewithdisabilitieswhoareunabletouseakeyboardormousecanshopwithoutanyhelp. Butvoiceshoppinghasitsdisadvantages.Unwanteddollhousesaren'tthebiggestproblem.It'susuallyveryeasytocancelanorderorreturnproducts.Thethingthatworriessomepeopleisthattheseassistantsarealwayslistening.Theyhavetobeabletorespondwhenyouwantthem.SotheylistenforAlexaorOKGoogleoranotherorder.Whentheyhearittheystartrecordingtheconversation.Somehaveworriedaboutwhathappensshoppinghabits?Andwhatifsomeonehacks入侵thedevice?TheCIAfoundawaytohacksmartTVstoturnthemintospiesthatlistenallthetime.Otherscoulddothesamewithanysmartdevice. Whatdoyouthink?Areyoureadytostartvoiceshopping? 1FromthepassageweknowthatAlexa. A.canlookafterthebaby B.cancookdeliciousfood C.isatoydollsoldonline D.isonekindofAIdevice 2TheunderlinedwordrareinParagraph2probablymeans. A.unusual B.expensive C.harmful D.impossible 3Whichofthefollowingisthebesttofillinthe▲inParagraph3? A.Convenienceisthemainadvantageofvoiceshopping B.Thecostofvoiceshoppingislowerthanotherways C.Thepopularityofvoiceshoppingisincreasing D.Thetechnologyofvoiceshoppingneedsimproving 4Paragraph4mainlytellsusthatwhenpeopletryvoiceshopping. A.AIsometimesforgetspeople'sorders B.personalinformationmightbehacked C.It'sdifficulttocancelorreturnproducts D.theneedsforproductscan'tbesatisfied

Samfindssweepingrobotsusefulandheplanstobuy_forhisgrandma. A.it B.one C.this D.that

如图所示AB为两个质量相等的小球由细线相连再用轻质弹簧悬挂起来在AB间细线烧断后的瞬间AB的加速度分别是

﹣ShallIlockthedoorbeforeIleavethemeetingroom? ﹣.I'llaskVickytocheckitwhensheleaves. A.You'dbetternot B.Goahead  C.Don'tbother D.Takeyourtime

已知二次函数y＝ax2﹣bx﹣2a≠0的图象的顶点在第四象限且过点﹣10给出下列叙述 ①式子b2＞8a ②式子a﹣b﹣2＜0 ③存在实数k满足x≤k时函数y的值都随x的值增大而增大 ④当a﹣b为整数时ab的值为1 其中正确的是

佳荣旅行社推出AB两种优惠方案 李阿姨带5名小朋友选哪种方案省钱

一个等腰三角形的顶角是98度那么它的一个底角是度．

已知函数fx＝|x﹣a2|+|x﹣2a+3|gx＝x2+ax+4a∈R． 1当a＝1时解关于x的不等式fx≤4 2若对任意x1∈R都存在x2∈R使得不等式fx1＞gx2成立求实数a的取值范围．

Wedon'tallowtakingmagazinesoutbutyou  copythearticleyouneedonthemachineoverthere.A.can B.must C.should D.would

道路交通安全法第四十七条规定机动车行经人行横道应减速行驶遇行人正在通过人行横道时应停车让行．一辆汽车以36km/h的速度匀速行驶驾驶员发现前方50m处的斑马线上有行人驾驶员立即刹车使车做匀减速直线运动若已知行人还需12s才能通过斑马线则刹车后汽车的加速度大小至少为

小李在景区销售一种旅游纪念品已知每件进价为6元当销售单价定为8元时每天可以销售200件．市场调查反映销售单价每提高1元日销量将会减少10件物价部门规定销售单价不能超过12元设该纪念品的销售单价为x元日销量为y件日销售利润为w元． 1求y与x的函数关系式． 2要使日销售利润为720元销售单价应定为多少元 3求日销售利润w元与销售单价x元的函数关系式当x为何值时日销售利润最大并求出最大利润．

有5张不透明的卡片除正面上的图案不同外其他均相同．将这5张卡片背面向上洗匀后放在桌面上． 1从中随机抽取1张卡片卡片上的图案是中心对称图形的概率为． 2若从中随机抽取1张卡片后不放回再随机抽取1张请用画树状图或列表的方法求两次所抽取的卡片恰好都是轴对称图形的概率．

某酒店要在楼梯上铺地毯如图这块地毯的长度是．

为了建设书香校园某班开展捐书活动班长将本班44名学生捐书情况统计如下 该组数据捐书本数的众数和中位数分别为

最近用手机APP买菜的人多了.手机菜场菜品丰富洗净配好预约送菜上门外国朋友对此也很感兴趣. 请你以ANewUseoftheMobilePhone为题写一篇110词左右的英语短文介绍手机买菜带来的便利让外国朋友了解中国人民生活中的这个新变化. ANewUseoftheMobilePhone

已知数列{an}的通项公式为an＝n+则a2＞a1是数列{an}单调递增的

身体是革命的本钱可中学生目前的健康状况让人十分堪忧.家长学校专家忧心忡忡.于是有人献良策将体育纳入高考.请结合实际谈谈你的看法作短文一篇将其发表. 注意 1短文词数不少于100 2可适当增加细节使行文连贯 3文章的开头已给出不计入总次数. Thefactthathighschoolstudentsarecurrentlyexperiencingasharpdeclineinhealthhasarousedwideconcernamongparentsschoolsandexperts. .

图1是由若干个小圆圈堆成的一个形如等边三角形的图案最上面一层有一个圆圈以下各层均比上一层多一个圆圈一共堆了n层．将图1倒置后与原图1拼成图2的形状这样我们可以算出图1中所有圆圈的个数为1+2+3++n＝． 如果图3中的圆圈共有13层． 1我们自上往下在每个圆圈中都图3的方式填上一串连续的正整数1234则最底层最左边这个圆圈中的数是 2我们自上往下在每个圆圈中按图4的方式填上一串连续的整数﹣23﹣22﹣21﹣20求最底层最右边圆圈内的数是 3求图4中所有圆圈中各数值之和．写出计算过程

下列运算正确的是

一个不透明的布袋中只装有红球和白球两种球它们除颜色外其余均相同．若白球有9个摸到白球的概率为0.75则红球的个数是．

如图所示斜面倾角为θ位于斜面底端A正上方的小球以不同的初速度v0正对斜面顶点B水平抛出小球到达斜面经历的时间为t重力加速度为g则下列说法正确的是

佳佳文具店购进AB两种款式的笔袋其中A种笔袋的单价比B种袋的单价低10%．已知店主购进A种笔袋用了810元购进B种笔袋用了600元且所购进的A种笔袋的数量比B种笔袋多20个．请问文具店购进AB两种款式的笔袋各多少个

用金属丝制成一个U型架一段细长棉线两端紧扣在U型架两臂上AB两点细线中点O处有一扣．将U型架浸入肥皂液中再取出U型架上形成的肥皂液膜如图所示细线被绷紧是因为液体表面层存在表面张力表面张力的作用是使得液面有的趋势用力拉动细线中点的扣至图中虚线位置肥皂液膜未发生破损肥皂液膜的内能将忽略肥皂液膜的蒸发影响

在棱长为9dm的正方体盒子中最多能放下个棱长是3cm的小正方体．

Birdscanflybecausetheyhavethestrongchestmuscleforflying. A.required B.provided  C.strengthened D.possessed

下列运算正确的是

如图MN是线段AB上的两点AB＝16MN＝6将线段AM绕点M旋转将线段BN绕点N旋转点A点B的对应点恰好重合记为点C设AM＝x． 1求x的取值范围 2过点C作CH⊥AB于点H若CM+MH＝CN+NH试判断△CMN的形状并说明理由 3在2的前提下以C为圆心CH为半径的圆的内接正三角形正方形正六边形边心距分别为d1d2d3求以d1d2d3为三边长的三角形面积．

WhenyouarriveinOxfordstopfirstattheOxfordVisitorInformationCentrelocatedinBroadStreet. Staffatthecentrearehappytoansweryourqueriesandofferthefollowingservices ●Informationonattractionstheatresconcertsandothereventsandentertainment ●BedandBreakfastreservationsinOxfordandelsewhereforpersonalcallers ●Acomprehensiverangeofmapsprintedguidespostcardsandsouvenirs ●BureaudeChangefacilities ●Informationonbustoursandexcursions Openingtimes ●Duringthesummermonths930am﹣500pmMondaytoSaturday ●1000am﹣100pmand130pm﹣330pmSundays&PublicHolidays ●Closed25thDecember﹣1stJanuaryinclusive. Telephone01865252200 Viewsofthetown TogetanoverviewbeforeyoubeginwalkingtryclimbingupCarfaxTowerinthecitycentre. OtherviewsoverthecityareavailablefromtheUniversityChurchofSt.MarytheVirginintheHighStreetandSt.MichaelNorthgateinCornmarket.Allofthesevantagepointshavesmalladmissioncharges. TheUniversity OxfordishometoaworldfamousuniversityandmostofthecollegesanduniversitybuildingsarelocatedinthecentreofOxfordwithineasywalkingdistanceofeachother. Don'tmisstheBodleianLibrarywhichhasitsownshopandthenearbyRadcliffeCamerawhichisnotopentothepublicbutiswellworthaviewfromtheoutside. NearbyinBroadStreetistheSheldonianTheatreavenueforofficialuniversityfunctionsaswellasavarietyofconcertsticketsavailablefromTheOxfordPlayhouseinBeaumontStreet. TheUniversityalsoownstheAshmoleanMuseumonBeaumontStreetoppositeThePlayhouseBritain'soldestpublicmuseum. 56.Thepassageistargetedat. A.studentswhowanttostudyatOxford B.visitorswhointendtovisitOxford C.companiesthatdecidetoexpandtourism D.foreignersthatpreparetosettleinBritain 57.WhatcanwelearnaboutOxfordUniversityfromthepassage? A.Thereisahightowerinthecentreofit. B.ItishometoBritain'soldestpublicmuseum. C.TheBodleianLibraryisnotopentothepublic. D.It'ssobigacampusthatbuildingsarefarfromeachother.

Therearesomevolunteersinthepark. A.表语 B.宾语 C.主语 D.定语

AsthetraditionalSpringFestivalisapproachingshopownersfromallwalksoflifeofferlargediscountshighsalesincomefromtheircustomers. A.inexpectationof B.incelebrationof  C.inexplanationof D.inpossessionof

如图所示在水平圆盘上沿半径方向放置物体A和BmA＝4kgmB＝1kg它们分居在圆心两侧与圆心距离为rA＝0.1mrB＝0.2m中间用细线相连AB与盘间的动摩擦因数均为μ＝0.2设最大静摩擦力等于滑动摩擦力若圆盘从静止开始绕中心转轴非常缓慢地加速转动用ω表示圆盘转动的角速度fA表示物体A与圆盘之间的摩擦力取g＝10m/s2． 1细线中出现张力时圆盘转动的角速度ω1 2AB两物体相对圆盘将要滑动时圆盘转动的角速度ω3 3在下列坐标图中分别画出AB两物体滑动前fA随ω2变化的关系图象

如图所示不带电的金属球B接地在B球附近放置一个带正电q的小球AA的重力不计．现由静止开始释放A球在A运动过程中下列说法正确的是

甲和乙的乘积为定值那么甲和乙成．

大小两个圆的半径分别是5厘米和3厘米大小两个圆的周长的比是面积的比是．

如图在固定斜面上的一物块受到一外力F的作用F平行于斜面向上．若要物块在斜面上保持静止F的取值应有一定的范围已知其最大值和最小值分别为F1和F2F1和F2的方向均沿斜面向上．由此可求出物块与斜面间的最大静摩擦力为

已知等边△ABC内接于⊙OD为弧BC的中点连接DBDC过C作AB的平行线交BD的延长线于点E． 1求证CE与⊙O相切 2若AB长为6求CE长．

若关于x的一元二次方程ax2﹣8x+4＝0有两个不相等的实数根则a的取值范围是．

下列说法正确的有 A．密立根油滴实验精确测定了电子电荷发现了电荷是量子化的  B．氢原子光谱包含红外可见光和紫外光  C．发生光电效应时使光电流为零的遏止电压与入射光的频率成正比  D．原子核核子数越多原子核越不稳定

﹣Shallwegotothesupermarketafterschool?Ineedtobuysomething. ﹣Let'smeetattheschoolgateat500p.m. A.Itdoesn'tmatter B.AreyouOK?  C.Whynot? D.That'sallright

如图所示A是地球的同步卫星B是地球的近地卫星C是地面上的物体ABC质量相等均在赤道平面上绕地心做匀速圆周运动．设ABC做圆周运动的向心加速度为aAaBaC周期分别为TATBTCABC做圆周运动的动能分别为EkAEkBEkC．不计ABC之间的相互作用力下列关系式正确的是 ρ

Thereareplentyofthingstobegainedfromgoingabroadnewfriendsnewexperiencesnewstories.Butlivinginanothercountrymaycomewithalessnoticeablebenefittoo.Somescientistssayitcanalsomakeyoumorecreative. Writersandthinkerslovetravellingabroad.ErnestHemingwayforexampledrewinspirationformuchofhisworkfromhistimeinSpainandFrance.AldousHuxleytheauthorofBraveNewWorldmovedfromtheU.K.totheU.S.inhis40stobranchoutintoscreenwriting.MarkTwainwhosailedaroundthecoastoftheMediterraneanin1869wroteinhistravelogueInnocentsAbroadthattravelisfataltoprejudicebigotryandnarrow﹣mindedness. Inrecentyearspsychologistsandneuroscientistshavebegunexaminingmorecloselywhatmanypeoplehavealreadylearnedthatspendingtimeabroadmayhavethepotentialtoaffectmentalchange.Ingeneralcreativityisrelatedtohowthebrainiswired.Neural神经的pathwaysaresensitivetochangenewsoundssmellslanguagestastessensationsandsightssparkdifferentsynapses神经突触inthebrainandmayhavethepotentialtorevitalize使恢复生机themind. Foreignexperiencesincreasebothcognitiveflexibilityanddepthandintegrativeness综合性ofthoughtsaysAdamGalinskyaprofessoratColumbiaBusinessSchoolandtheauthorofnumerousstudiesontheconnectionbetweencreativityandinternationaltravel.Cognitiveflexibilityisthemind'sabilitytojumpbetweendifferentideasakeycomponentofcreativity.Butit'snotjustaboutbeingabroadGalinskysaysThekeycriticalprocessismulticulturalengagementimmersion浸入andadaptation.Someonewholivesabroadanddoesn'tengagewiththelocalculturewilllikelygetlessofacreativeboostthansomeonewhotravelsabroadandreallyengagesinthelocalenvironment.InotherwordsgoingtoCancunforaweekonspringbreakprobablywon'tmakeapersonanymorecreative.ButgoingtoCancunandlivingwithlocalfishermenmight. Theresearchersalsofoundthatthemorecountriestheexecutiveshadlivedinthemorecreativethelinestendedtobe﹣butonlyuptoapoint.Thosewhohadlivedandworkedinmorethanthreecountriesthestudyfoundstilltendedtoshowhigherlevelsofcreativitythatthosewhohadn'tworkedabroadatallbutlesscreativitythattheirpeerswhohadworkedinasmallernumberofforeigncountries.Theauthorsassumedthatthosewhohadlivedintoomanycountrieshadn'tbeenabletoproperlyimmersethemselvesculturallytheywerebouncingaroundtoomuch.Itgetsbacktothisideaofadeeperleveloflearningthat'snecessaryfortheseeffectstooccurGalinskysays. Ofcoursealthoughanewcountryisaneasywaytoleaveasocialcomfortzonetheculturalengagementassociatedwithcognitivechangedoesn'thavetohappenabroad.Ifaplaneticketisn'tanoptionmaybetrytakingthesubwaytoanewneighborhood.Sometimestheresearchsuggestsallthat'sneededforacreativeboostisafreshculturalscene. 61.TheexamplesofthethreewritersinParagraph2areto. A.showhowtravellingabroadinspiresone'sbrain B.explainthecreativebenefitsofinternationaltravel C.illustrateprejudiceandnarrow﹣mindednesscanharmcreativity D.discusswhywritersandthinkerstendtobemoreopen﹣minded 62.ItcanbelearnedfromParagraph3that. A.neuralpathwaysarebirthplacesofcreativity B.creativeisresponsibleforrevitalizingthemind C.creativitycanbedevelopedbychangesoftheenvironment D.neuralpathwaysallowdifferentsynapsestoworkefficiently 63.WhatisthekeycriticalprocessaccordingtoGalinsky? A.Thedeepinvolvementwithforeignculture. B.Travellingabroadforarelativelylongerperiod. C.Themind'sabilitytojumpbetweendifferentideas. D.Livingintheforeigncountryinsteadofjusttravellingthere. 64.Whichofthefollowingcouldbethemostsuitabletitleforthepassage? A.Leaveyoursocialcomfortzone B.Foramorecreativemindtravel C.Putdownyourworkandgotoyourneighborhood D.Foranartisticinspirationgotomoreforeigncountries.

一张长方形纸长8厘米宽6厘米．用它剪成一个最大的正方形正方形的周长是厘米面积是平方厘米．

这位老人习惯于早上7点起床

我国古代数学著作孙子算经中有多人共车问题今有三人共车二车空二人共车九人步．问人与车各几何其大意是每车坐3人两车空出来每车坐2人多出9人无车坐．问人数和车数各多少设车x辆根据题意可列出的方程是

⊙O过点BC圆心O在等腰直角△ABC内部∠BAC＝90°OA＝1BC＝6则⊙O的半径为

Thenumberonereasonthe16﹣year﹣oldsingerexplodedinpopularityishisrawsingingtalent. A.that B.whether C.how D.why

1Decemberisthemonthoftheyear. 2Shewantsmetomeetanoldfriendof. 3I'msorrythatthingshadtoendlikethis. 4Hetakesgreatinhischildren'ssuccess. 5Thecompetitionisopentokidssixandtenyearsofage.

PleaseTakemyChildrentoWorkDayPTCWDayfirstbeganasaholidayforhard﹣workingandtiredstay﹣at﹣homemotherstotakeadayoff.Nowthisdayisfitforanyparent.Itwascreatedin2003andiscelebratedeachyearonJune25butitisn'tapublicholiday.Itencouragesfriendsandfamilytotakecareofthechildrensothatthestay﹣at﹣homeparentcanhavesometimetorelax. KamehamehaDayisheldonJune11eachyear.KamehamehatheGreatwasthemonarch君主ofHawaii.Heisfamousandrespectedforestablishing建立theKingdomofHawaiiin1810.KamehamehaDayisapublicholidayinHawaiiandthisisadayoffforpeopleSchoolandmostbusinessesareclosed. D﹣DayiscelebratedintheU.S.tomemorizetheNormandylandingsinFranceonJune61944.OnthedayAmericanarmyandotherAlliedforces盟军foughthardandtheWorldWarⅡWWⅡinEuropewasoversoon.Itisnotapublicholiday.Businesseshavenormalopeninghours. FlagDayiscelebratedonJune14eachyeartohonortheUnitedStatesflag.OnthesamedaytheUnitedStatesArmycelebratesitsbirthday.AlthoughFlagDayisagreatcelebrationacrossthecountryitisnotapublicholiday. 1Ifyouareastay﹣at﹣homeparentwhatcanyoudotorelaxonPTCWDay? A.Takeadayoff. B.Gotoworkearlier. C.Lookafterchildren. D.Dosomehousework. 2Whichisapublicholiday? A.PTCWDay. B.KamehamehaDay. C.D﹣Day. D.FlagDay. 3WhenistheUnitedStatesAmy'sbirthday? A.OnJune6. B.OnJune11. C.OnJune14. D.OnJune25. 4WhatcanweknowaboutD﹣Day? A.ItiscelebratedinFrance. B.TheWWⅡendedbefore1944. C.Businessesareclosedforit. D.TheNormandylandingshappenedin1944.

﹣IlovetheInternet.I'vecometoknowmanyfriendsontheNet. ﹣.Fewofthemwouldbecomeyourrealfriends. A.That'sforsure  B.It'snotthecase  C.Icouldn'tagreemore  D.I'mpleasedtoknowthat

滑雪运动中当滑雪板压在雪地时会把雪内的空气逼出来在滑雪板与雪地间形成一个暂时的气垫从而大大减小雪地对滑雪板的摩擦．然而当滑雪板相对雪地速度较小时与雪地接触时间超过某一值就会陷下去使得它们间的摩擦力增大．假设滑雪者的速度超过4m/s时滑雪板与雪地间的动摩擦因数就会由μ1＝0.25变为μ2＝0.125．一滑雪者从倾角θ＝37°的坡顶A处由静止开始自由下滑滑至坡底BB处为一光滑小圆弧后又滑上一段水平雪地最后停在C处如图所示不计空气阻力坡长L＝26m取g＝10m/s2sin37°＝0.6cos37°＝0.8求 1滑雪者从静止开始到动摩擦因数发生变化所经历的时间 2滑雪者到达B处的速度 3滑雪者在水平雪地上运动的最大距离．

因式分解﹣x2+2＝．

如果＝yxy均不为0那么x和y成比例如果＝x那么x和y成比例．

Notmanyofusreallygottoseethehardworkthathappensthescenestomakeourfavoritemoviescometolife. A.without B.to C.behind D.by

下列调查中调查方式最适合普查全面调查的是

一个三角形三个内角的度数比是234这是一个三角形．

笑笑在跑道中央位置向西走了25米记作﹣25米然后再调头往东走了36米与中央位置相比应记作米

Theseedvault种子地窖 Alotofcountriesneeddifferentkindsofseedssothattheycanplantthemagain.ThereisanimportantreasonforthisSometimesplantscan'tgrowinacountrybecauseofbadweatherordiseasesofarmersneednewseeds. Youcankeepseedsinaseedvault.It'saplaceataspecialtemperature.Theseedsdon'tgrowbuttheycanliveforalongtime.Norwayhasthebiggestseedvaultintheworld﹣theSvalbardGlobalSeedVault﹣andithasseedsfromalotofdifferentcountries. ThevaultisontheislandofSpitsbergen.TheislandisaboutonethousandkilometersfromtheNorthPole.It'saverycoldplacesoit'sgoodforseeds.Abovethegroundthedoorwayissmallbutinsidethebuildingishuge.Youwalkdownalongcorridor走廊whichisonehundredandthirtymetersinsideamountain.Attheendofittherearethreelargeareaswithseeds. Thereareabouthalfamillionkindsofseedsinsidethevault.ForexampletherearekindsofseedsforricefromAsiaandAfrica32kindsofseedsforpotatoesfromIrelandandseedsfordifferenttomatoesfromtheUSA. Theseedvaulthasspaceforalotmoreseeds.Youcanputabout2.2billion十亿seedsinside.Theseedscanlivehereforthousandsofyearsbecauseofthecoldtemperatureof﹣18℃.Sointhefuturehumanscangrowanyseedtheywant.Inotherwordstheseedvaultisthedifferencebetweenlifeanddeath. 1Whycan'tplantsgrowinacountry?within6words 2Whereisthebiggestseedvaultintheworld?within2words 3HowfaristheSvalbardGlobalSeedVaultfromtheNorthPole?within4words 4Howmanyseedscanbeputintheseedvault?within3words 5Whatplaceisaseedvault?within12words

跳伞表演是人们普遍喜欢的观赏性体育项目当运动员从直升飞机由静止跳下后在下落过程中不免会受到水平风力的影响下列说法中正确的是

﹣WhendidNeilArmstrongwalkonthemoon? ﹣July20th1969. A.In B.At C.For D.On

以一个长方形的一条长为轴旋转一周得到的立体图形是

Believeitornotmanyfrozenvegetablesareasnutritiousasfreshonesandsometimesevenmoreso. A.particularly B.occasionally  C.equally D.eventually

Americacontinuestoleadtheworldasadestinationforinternationalstudents.Lastyearabout900000foreignstudentswerestudyingintheUnitedStatesabouthalfofthemfromAsia.ButagrowingnumberofAsianstudentsarelookingtoanEnglish﹣speakingcountrymuchclosertohome﹣thePhilippines. Theislandnationof100millionisquicklybecomingtheeducationcenterofAsia.Thecountry'slowpricesopencultureandqualityschoolsareattractingrecordnumbersofforeignstudents.KoreansareleadingthewayaccordingtoJoseL.CuisiathePhilippinesAmbassadortotheUnitedStates. ThePhilippinesisinauniquepositiontobenefitfromtheglobaldemandforEnglisheducation.AmericancolonialismbroughttheEnglishlanguagehereintheearlytwentiethcentury.AlthoughitisnotthenativelanguageofmostFilipinosEnglishisanofficiallanguagehere.Morethan60yearsafterindependenceFilipinosstillspeakEnglishwithastrongAmericanaccent.TodaythePhilippinesmarketsitselfastheworld'sthird﹣largestEnglish﹣speakingcountry. ThetruthisweactuallyhavemorepeoplewhospeakEnglishinthePhilippinesthanthenationallanguage.EnglishislearnedevenoutsideofschoolbecausealotofthecommunicationsdoneinEnglish.PublicsignstelevisionandtheInternetareallinEnglish. LowpricesanditslocationinAsiahelpedtoproducetheeducationexplosioninthePhilippines.ThecapitalManilahascheapnon﹣stopflightstoTokyoSeoulandotherAsiancapitals.TherisingU.S.dollarhasmadeAmericaneducationmoreexpensivethaneverbefore. TherearehundredsofprivateandpublicschoolsinthePhilippinesthatteachEnglishorteachinEnglish.MoreadvancedstudentscantakeregularuniversityacademiccoursesinEnglish.Othersstudyatbeachsideresortswheretheymixlanguagestudywithvacation.SomeKoreanfamiliesevenmovetothePhilippinessotheirchildrencanlearnEnglishinpublicschools. AsintheU.S.schoolsinthePhilippinesrangefromworld﹣classtolow﹣qualitydiplomamills.PearlGaborno﹣IlustreistheChiefAcademicOfficerattheTESOLTrainingCorporationinManila.Shesaysforeignstudentsshouldchoosetheirschoolscarefully.Sherecommendsprogramsthatuseamodernteachingstyle. Onedoesn'treallylearnlanguagebystudyinggrammarwelearnlanguagebyactuallyusingit.InmostAsiancountriesstudentslearnEnglishthroughgrammarandtranslationfromthemotherlanguage.InthePhilippinesstudentsareencouragedtopracticespeakingEnglishinreal﹣lifesituations.Ingeneralthereislessemphasisongrammaranderrorcorrection. ThePhilippines71Englishlearners TheeducationcenterofAsia ●MoreandmoreAsianstudents72tolearnEnglishinthePhilippines. ●ThePhilippines'pricesare73anditsculturequalityeducationappealtoforeignstudents. The74ofstudyingEnglishinthePhilippines ●EnglishisanofficiallanguageinthePhilippinesandFilipinoscanspeak75EnglishbecauseoftheUScolonialism. ●Englishcanbelearnedfromallkindsofcommunicationand76. ●Lowcostsandthefavorablelocation77therapiddevelopmentofthePhilippines'internationaleducation. ThestudyofEnglishinthePhilippines ●TherearemanyschoolsanduniversitieswhereyoucanlearnEnglish. ●MoreadvancedstudentscantakeuniversityacademiccoursesinEnglish78whileothersstudyduringvacation. ●It'srecommendedthatEnglishshouldbelearnedthroughprogramstaughtina79way. ●Youneedn'tworryaboutmaking80andareencouragedtopracticeEnglishthroughactualuse.

如图甲所示一长为l的轻绳一端穿在过O点的水平转轴上另一端固定一质量未知的小球整个装置绕O点在竖直面内转动．小球通过最高点时绳对小球的拉力F与其速度平方v2的关系如图乙所示重力加速度为g下列判断正确的是

他的梦想将会实现.

Cathyisafraidofthedog.Shewillrunaway  sheseesit.A.eversince B.although C.assoonas D.sothat

如图一束单色光射入一半径为0.1m玻璃球体入射角为60°已知光线在玻璃球内经一次反射后再次折射回到空气中时与入射光线平行．求 ①此玻璃的折射率 ②光在玻璃球内只有一次反射情况下的传播时间．

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. Inordertoencouragethestudentstakeoutdoorexerciseourschoolorganizedamountain﹣climbingactivityinApril10.Hundredsofustookpartinit. At800amwegatheratthefootofDaqingMoutainandsetoutforthetopinhighspirit.Allthewaywewerechattingsingingbutlaughingenjoyingthefreshairandthebeautifulscenery.Whensomefellbehindotherswouldcomeandofferhelp.About2hourslateweallreachedthetop.Bathinginsunshinewejumpedandcheeredwithjoy. Theactivitybenefitedusalot.Notonlydiditgetusclosetothenatureandgiveusrelaxationfromheavyschoolworkitalsopromotedyourfriendship.Whatawonderfullytime!

注意运算顺序． ①2.3+5.5﹣2.3+5.5 ②3.6×5.5÷3.6×5.5 ③6.8÷3.4×6.8÷3.4 ④5.5﹣2.3+5.5﹣2.3 ⑤3.6×5.5÷3.6×5.5 ⑥6.8÷3.4×6.8÷3.4

在20km的环湖越野赛中甲乙两选手的行程y单位km随时间x单位h变化的图象如图所示根据图中提供的信息下列说法中错误的是

Forthousandsofyearshumanshaveexplored探索theEarth.Nowadaysweareexploringspace.Astronomers天文学家arethemodern﹣dayexplorersNowmanyastronomersarelookingfornewplanetsandnewplacesforhumanstoliveinthefuture.Butwheredoastronomersstartlooking? Firstofallastronomerslookforastar.That'sbecauseourownEarthmovesaroundastartheSun.Moreimportantlyitisthecorrectdistance距离fromtheSunforheatandlight.SowhenastronomershavefoundthestartheylookattheplanetsarounditInrecentyearsastronomershavefoundnearly400newplanetswithstars.Howevermanyoftheseplanetsareeithertooneartothestarortoofaraway. Howeveriftheplanetisinagoodpositionastronomerslookforthreekeythingswaterairandrock.Waterisimportantbecausealllifeneedswater.Humanscandrinkitandtheycanalsogrowplantswithwater.Andplantsproduceairforhumanstobreatheandfoodtoeat.Rockonaplanetisalsoimportant.That'sbecausethereisoftenwaterundertherock. Aftermanyyearsofscrutinizing.astronomershavefoundaplanetthatissimilartotheEarth.It'sGliese581gandit'snearastar.Theastronomersthinkithaswaterandrockandtheaverage平均的temperatureisbetween﹣31℃and﹣12℃.That'scoldbutnotcolderthanAntarcticaortheArcticCircleforexample.Gliese581gisbiggerthantheEarth.AyearonGliese581gisonly37Earthdaysinsteadof365.ButastronomersdonotthinkthesearebigdifferencesandsomeofthemthinkGliese581gwillbeanewEarth.HoweverGliese58IgistwentylightyearsfromtheEarth. 1Whatdoastronomershavetofindfirstbeforestartingtolookforanewplaceforhumanstolive? A.newstar. B.Anewplanet. C.Someheat. D.Somelight. 2Whatdoestherockonaplanettellus? A.Thestarisinarightposition. B.Wemaydiscoverwaterunderit. C.TheplanetistooneartotheSun. D.Therecanbeairaroundtherock. 3Whatdoestheunderlinedwordscrutinizingmeaninthelastparagraph? A.discussing. B.waiting. C.looking. D.traveling. 4What'sthemainideaofthetext? A.Gliese581gisalreadyanewEarth. B.ThereareplanetssimilartoourEarth. C.Waterairandrockareimportant. D.AstronomersarelookingforanewEarth.

Successfulanduniquepeoplealwaysdeterminewhotheyarecommonpeoplealwayschangetheirfaith. A.until B.before C.although D.while

Iwanttorelateaneventwhichhappenednearly10yearsago.Iwas9atthattimestillasmallchildbackthen.It41inavillageinAlibaugaplaceinMaharashtrainIndiaduringthe42holidays.MymomandIwereatthe43forquitesometimewhenwedecidedtogoback.Itis44thatwewouldreachthehotelafterwalkingforaboutten45.Mymomaskedherfriend46oursandals凉鞋were﹣wewerestillatthebeach.Herfriendpointed47somedirectionandmymomthenwentthere.Howeversoonmom48wewerelost.Wewerenowinaquiteabig49.Andsinceitwasnoonthegroundwas50hotandmymomhadtocarryme.Iwasscared.Ididn'tunderstandthenour51﹣momwasinabigjunglewithher9﹣year﹣oldkidandcompletelylost.Iwas52anddidn'tknowwhattodo.SoIbeganto53.AsachildtheonlyprayerIknewwas'OurFather'and'GodOurProtector'.54whichofthetwoIprayedbutIdidremembermymother55methatassoonIhadfinishedprayingawomanstoodbeforemymother.Thewomangavemomhersandalsandtoldmymomthatshehad56anentirevillageandcurrentlywasina57village.Thatwoman58tookusbacktothehotelwewerestayingat.A59actmakesabigdifference.Iwillrememberthat60womanforever.Itwasshewhohelpedmombackthen.41.A.brokeout B.tookplace C.occurredto D.brokedown42.A.spring B.summer C.autumn D.winter43.A.beach B.jungle C.hotel D.village44.A.regular B.ordinary C.unusual D.normal45.A.seconds B.days C.minutes D.weeks46.A.that B.when C.where D.what47.A.for B.from C.to D.in48.A.announced B.ignored C.realized D.remembered49.A.jungle B.desert C.village D.river50.A.hardly B.quite C.ever D.never51.A.benefit B.question C.state D.trouble52.A.confident B.afraid C.intelligent D.brave53.A.shout B.pray C.scream D.yawn54.A.forgot B.understood C.explained D.ignored55.A.telling B.warning C.blaming D.apologizing56.A.walked B.jumped C.crossed D.flew57.A.dangerous B.same C.different D.grand58.A.accidently B.disappointedly C.freely D.safely59.A.small B.funny C.elegant D.possible60.A.outstanding B.easygoing C.beautiful D.kind

先化简再求值1﹣÷其中a＝﹣2b＝5﹣．

﹣32的值是

已知函数fx＝lnx﹣x+aa∈R． 1若fx≤0恒成立求a的取值范围 2若gx＝fx﹣试研究gx的单调性 3若x1x2是函数fx的两个零点且x1＜x2求证x1x2＜1．

地球上海洋的面积大约是三亿六千一百万平方千米写作平方千米省略亿后面的尾数约是亿平方千米．

如图▱ABCD的两条对角线相交于O点过O点作OE⊥AB垂足为E已知∠DBA＝∠DBCAB＝5． 1求证四边形ABCD为菱形 2若sin∠ADB＝求线段OE的长．

某校数学综合实践小组的同学以绿色出行为主题•把某小区的居民对共享单车的了解和使用情况进行了问卷调查在这次调查中发现有20人对于共享单车不了解．使用共享单车的居民每天骑行路程不超过8千米并将调查结果制作成统计图如图所示． 1本次调查人数共人使用过共享单车的有人 2将条形统计图补充完整则使用共享单车骑行的居民每天骑行路程的中位数落在范围内 3如果这个小区大约有3000名居民请估算每天骑行路程不超过4千米的有多少人

一个圆柱的侧面展开是正方形已知圆柱底面半径是4厘米圆柱的高是厘米．

如图所示A为地球同步卫星B为在地球赤道平面内运动的圆轨道卫星AB绕地心转动方向相同已知B卫星轨道运行周期为2小时图示时刻A在B正上方则

如图甲所示矩形导线框abcd固定在匀强磁场中磁场的方向与导线框所在的平面垂直磁感应强度B随时间变化的规律如图乙所示规定垂直纸面向里为磁场正方向顺时针方向为感应电流i正方向水平向右为ad边所受安培力F的正方向．下列图象正确的有

张老师买了2个篮球和8副乒乓球拍一共花了360元钱1个篮球的价钱是一副乒乓球拍价钱的4倍篮球和乒乓球拍的单价各是多少元

一次函数y＝﹣x+1的图象不经过的象限是

某物体质量为1kg在水平拉力作用下沿粗糙水平地面做直线运动其速度﹣时间图象如图所示根据图象可知

已知函数fx＝+x3+sinx其导函数为f′x则f2020+f′2020+f﹣2020﹣f′﹣2020的值为

Growingupinamilitary军人的familyImovedalot.Imostlywentto1withotherkidswhoseparentswerealsointhemilitary.Butwhenmydad2fromthearmyaftertwentyyearsofserviceIfoundmyself3acivilian平民的schoolwithtwelve﹣year﹣oldswhosharednosimilarlifeexperiencewithme. Iwasastrangerinastrangeland.Everyoneinmyclasshadgrownuptogetherandtheyhadnoroomto4foranewcomer.Iworedifferentclotheshaddifferentthoughtsandspokewithanaccent.I5forthefirstfewweeksofschool.Ihadnofriendsnoactivitiesandno6ofabrightfuture.TodealwithitallIbegan7inmydiaryeveryday﹣storiesofadventureofoldfriendsoffeelingsthatIcouldnotspeak.IwroteasifmylifedependedonitasiftheverynextbreathItookcouldnothappen8Iwrotedownwords. OnedaymyteacherMrs.BushcametomeandaskedwhyIalwayssattherewritinginsteadofplayingwithothers.ItoldherIenjoyedwritingand9writingtoplaying.Shesmiledatmeandwalkedaway.AboutthreeweekslaterMrs.Bushgaveusawritingassignment.Iwas10thatIcouldnowparticipateinsomethingIknewIexcelledin.ThatnightIworkedandworkedontheessay.Iwrotewithgreat11.Itwasmyonechancetofeelimportantand12bytheclass. AfewdaysafterwehandedinourassignmentsMrs.Bushcalledmeuptothe13oftheclassroom.IstoodbeforethirtypairsofeyeslookingatmeandIgot14.WasIintrouble?DidIdosomethingwrong?ThenMrs.Bushtoldtheclasshowmuchshe15alltheworkthatwentintotheessayandeveryonehaddoneagreatjob.Butshesaidonestudentstood16asanexcellentwriteronewithimaginationcreativityandwordmastery.Thatstudentwasme!TheclassclappedpolitelyandMrs.Bushhandedmemypaperwiththefollowing17onitMalindayouareanexcellentwriter.Youfillyourpaperwiththebreathingofyourheart.Pleasekeeponwritingandshareyour18ofwritingwiththeworld.Iamproudofyouandgladyouareinmyclass. Mrs.Bushhelpedmefeelasenseof19aplaceofpurposeandawaytosurviveatransition转移过渡inlife.Shehelpedmegain20inmyselfthatstayedwithmebeyondsixthgrade. 1A.church B.school C.war D.work 2A.separated B.withdrew C.quit D.retired 3A.visiting B.attending C.running D.leaving 4A.build B.preserve C.take D.spare 5A.struggled B.played C.fought D.exercised 6A.memory B.control C.promise D.need 7A.reading B.drawing C.writing D.copying 8A.unless B.once C.while D.after 9A.compared B.applied C.turned D.preferred 10A.astonished B.satisfied C.excited D.embarrassed 11A.anxiety B.curiosity C.wonder D.passion 12A.impressed B.accepted C.challenged D.envied 13A.front B.corner C.door D.outside 14A.annoyed B.disappointed C.worried D.surprised 15A.appreciated B.expected C.recognized D.enjoyed 16A.out B.up C.by D.off 17A.descriptions B.remarks C.suggestions D.accounts 18A.advantage B.purpose C.gift D.idea 19A.responsibility B.belonging C.devotion D.relief 20A.interest B.imagination C.creativity D.confidence

实数xy满足则z＝y﹣4x的取值范围是．

﹣64的立方根是．

某超市用1200元购进一批甲玩具用800元购进一批乙玩具所购甲玩具件数是乙玩具件数的已知甲玩具的进货单价比乙玩具的进货单价多1元． 1求甲乙玩具的进货单价各是多少元 2玩具售完后超市决定再次购进甲乙玩具甲乙玩具的进货单价不变购进乙玩具的件数比甲玩具件数的2倍多60件求该超市用不超过2100元最多可以采购甲玩具多少件

在[﹣11]上随机取一个数k则事件直线y＝kx与圆x﹣132+y2＝25相交发生的概率为

Youshouldneverblametheboyfortheresultofthetestforhehisbestthoughallareinvain. A.wastrying B.tried C.hadtried D.hastried

如图是由5个相同的小立方块搭成的几何体这个几何体的左视图是

一个数0除外除以等于把这个数扩大5倍．判断对错

﹣WhereisMike? ﹣IsawhimwithMr.Smithinthehallwaysjustnow. A.totalk B.talking C.talked D.talks

静止于粗糙水平面上的物体受到方向恒定的水平拉力F的作用其大小随时间变化如图甲所示．在拉力F从零逐渐增大的过程中物体的加速度随时间变化如图乙所示g取10m/s2．则下列说法中错误的是

Everypersonhasagreatdealoflovetogive.1Hereisageneralguidetoloving. Sayit.WhenyousaythewordsIloveyoumakesureyoureallymeanitandarewillingtodoanythingforthatspecialperson. 2Ifyoulovesomeoneyoushouldunderstandhowtheyfeelwheretheycomefromandwhotheyare.Realizehowtheycouldalsoloveyoubackjustaswell. LoveUnconditionally.Givingunconditionalloverequiresyoutolovewithoutanyexpectations. 3Itseemsdifficulttoonlyloveandnotdemandanythinginreturnintoday'sworldwhereeveryoneisselfish.Butevenintheworldweseemanyexamplesofunconditionalloveforexampletheloveamothergivestoherchildandthelovebetweentwolifepartners.Toloveunconditionallyyouwillhavetolearntosacrifice牺牲yourselfandyourdesiresandalsorealizethatsomeonemayhaveadifferentwayofshowinghisandherloveforyou.4. Realizeitcanbelost.Ifyourealizeyoucanlosetheoneyoulovethenyouhaveagreaterappreciationofwhatyouhave.5Don'tmakeidolofthepersonyoulove.Thiswillplacethemunderunnecessarypressureandwilllikelyresultinyoulosingthem.Neverstoploving.Evenifyouhavebeenhurtbefore.Youshouldnotstopgivinglove. A.Trylovingjustforthesakeoflove. B.Putyourselfinsomeoneelse'sshoes. C.Therearemanydifferentwaystoexplainlove. D.Thinkhowluckyyouaretohavesomeonetolove. E.Donotexpecttobelovedbackinexactlythesameway. F.Itdoesn'tmakeyouabadpersontodesiresomeoneelse'slove. G.Therearemanydifferentwaystolovesomeoneorevenyourself.