因为△ABC是锐角三角形，所以A=7分(2)设AMB=0，1·cos(π-0)3+121·cos0.9分所以c²+26²+310分93c²+6b² =2a²+9.11分(3）由(2)及正弦定理知：3sin²C+6sin²B=2a²+9，sin²Asin²A:a²(4 sin²C+8 sin²B-2)=9.9`.a²13分4 sin²C+8sin²B-21-cos2C1-cos2B又4 sin²C+8sin²B-2=4+8-2=4-2cos 2C-4cos 2B22=4-2cos(2A+2B)-4cos B=4+cos 2B+√3sin 2B-4cos 2B=4+2√3 sin(2B-)15分锐角三角形△ABC，B>0
ABx由选项B知，AP=（cos0,sin0,4)，AC=（4,4,0）.AP.ACAC4cos0 + 4sinθ AC=所以向量AP在向量AC方向上投影向量为：AC[AC√4²+4²+0√2sin(0+)AC√2sin(0+π)√2又因为=，即0=时，取等号，所以AP在面ABCD上88由选项B建系可知，A(0,0,0)，C(4,4,0),E（4,2,4)，若P是棱AB的一点，则令P(t,0,4)，则AP=（t，0,4)(0≤t≤4)，CE=(0,-2,4)，AP.CE所以cosAP，CE=168(0≤t≤4)，[AP|CE√t²+16×√（-2)²+4²√5√t+16故选：ABC12.0【分析】直线l的一个方向向量m=（2,-1,3）且过A（0,y,3）和B（-1,2，2)，有AB、m共线即有AB=kn，列方程求参数y、2进而求得y-由A（0,y，3）和B（-1,2,2)，有AB=（-1,2-y，x-3)又，直线l的一个方向向量为m=（2，-1,3）可设AB=km(2k=-1有-k=2-y，解得3k=z-3y-z=0故答案为：0【点晴】本题考查了应用向量共线求空间向量坐标参数；结合直线方向向量与其上两点所表示向量共线，求坐标参数13.12【分析】利用捆绑法结合倍缩法可得出不同的下锅顺序种数根据题意，将香菌、新笋、豆腐干三种原料进行捆绑，且这三种原料无顺序，
工.读后续写主题：重建农场易读度：83.9阅读下面材料，根据其内容和所给段落开头语续写两段，使之构成一篇完整的短文。grandfather， Stan. One evening, Chuck and Peter asked their grandfatherabout thenumberone activityonhisbucketlist（人生愿望清单）．"Iwant torebuild my dad's farmhouse and maintain it. It's a shame I could never do it,"hesighed.Stanworkedhardasacarmechanic,buthisearningswereneverenoughtomaintainsuchahugefarmMonths passed and there was no mention of the farm again. Stan andKyle continued working in their car repair shop, while Chuck and Peter workeddowntown. On Stan's 75th birthday, Chuck and Peter decided to give him asurprise.
(A)5.Why are theperformancesmentioned in一阅读(A)1.Onwhich daywillyoubeable to taste the阅读paragraph 2?local cuisine?A.To show theimpact of Guttlein'swork.A. Day 1.B.To compareArgentine and ColombianB. Day 2.artists.C. Day 3.C.To highlight the unique sound of theD. Day 4.bandoneon.D.To stress the importance of traditionalinstruments.(A)6.What can we know from paragraph 3?一阅读一阅读D)2.Where will you stay the longest if you joinA.Guttlein possessed inborn musicalthe trip?sensibility.A.At CameronLodge.B.Guttleinfeltdiscouraged by theB.AtAntelope Canyon.repetitivework.C.In Sedona,Arizona.C.Thetwoluthiershad an advantageoverD.In Page,Arizona.Guttlein.D.Thetwoluthierswereunwillingto teachGuttlein.一阅读(C3.How manyplaces canyou visit atmost阅读D)7.Whatdoes the descriptionof Guttlein'sin a day?workshop highlight?A. One.A.The difficulty ofmanagingfinances.B. Two.B.Thevarietyof tuningtools available.C.Three.C.Thehigh-technature of theworkspace.D.Four.D.The conventional feelof theworkspace.Damian Guttlein,52,held an old instrument called the bandoneonInDecember 2024.NASA'sParker SolarProbe came within 3.8millionand tapped on one ofits buttonsThenote soundedlike two notesat oncemiles of the sun’s surfacemarking humanity's closest approach ever.slightly off-key.Withaquickmovement ofhiswrists.heremoved theouterAsit flew around the sun,Parker also set a record for the fastest一阅读buttoncaseWithflbeanscraping（）tthne that crrespn一阅读human-made object,reaching an incredible speed of430.000mph.To getto the note hedjust played,slowly removing a thin layer of steel.Then,heso close,the Parker Solar Probe had to stand the sun’s extreme heat andplayed thesamenoteagainltwasnowclearandsingularwaveringgetyharmfulrayslikeno spacecraft before it.Scientists didn’t knowwhetherin the air like the voice of a lonely singer.There was no electronic tuner inParker survived orits conditionuntil about three days later,whenit sent itssight.Recently.the distinctive sound has increasingly been used in recordingsfirst signal back toEarth after itsflybyand live performances ofArgentine artistsin modern styles such as rock.Parker was launchedin2018aspart ofagroundbreaking mission topop,and even trap.He cited a performance by the Argentine DJ Bizarrap andstudy the sun.The goal is to better understand long-standing mysteries,Colombian singerShakira at the 2023LatinGrammy Awards and a concertsuch aswhy the sun'sextended atmosphereis hotter than its surface and therecording of the rock star Conociendo Rusia.All featured bandoneonsBtuned by Guttlein.But the secret was that these instruments had been allsolar storms，which can cause stunning,widespread auroras（极光）whiletuned for decades by twolthiers（弦乐显制作者）Italian-born Ricardoalsoposing a threat to power networks andradio signals.Romualdiand Fabio Fabiani,known together asLosTanos"For the pastyearsParker hasbeen steadily geting closer to the sun.Romualdi was Guttlein's childhood neighbor.As a child,GuttleinIn2021itmadehistory asthefirst spacecraft to enter the sunsupperwatched the luthier with curiosity,in histwenties,Romualdi brought himtoLosTanosworkshop forthefirst timeInitiallyhe swept thefloorsandatmosphere,alsoknown as the corona（日冕）NASA said Parkerwill start sending back data collected during itshandlednearly every task except tuning But he was good with his hands,having learnedmetalworking froma young age.After only afewmonthsinflybys of the sun at theendofJanuary 2025theworkshop,he knew he'd found his callingUntil recently,we simply didnt possess the technology.In 2018,thatNow that themastersare one,Gutleincontinues theLosTanos traditionall changedwith the launch of the Parker Solar Probe, said Nour Rawafi,His own workshop is a small room beside his home.It's a neat space,theproject scientist for NASA'sParker Solar Probe mission at the Johnsperhaps because he doesn’tneed many tools besides a metal file, someHopkins University Applied Physics Laboratory (APL).He added,“It hasplatesandhisearIn the drawers layspare patstoothy metal platesflestransformedour understanding of the sun.Parker was equippedwith awood pieces,and buttons.Normally,musicians come to him.But sometimesspecial heat protector that reflects light,absorbs heat and cools through ahe stays in another country for a few monthsfixing the instruments.network ofwater-filledpipes,according toRawaf.B)4.WhatcanbeinferredfromGuttlein's一阅读B)8.Why can theParker SolarProbe getclosetuning experience?阅读to the sun?A.He is more theoretical than practical.A.It can travel in a straight line.B.Heprefers traditional overhi-techB.It can resist high temperatures.methods.C.Itcansend itssignalsbacktoEarth.C.He is experienced in playing theD.It can rely on the assistance frombandoneon.planets.D.He combines electronic tuningwithmanual work.
1、明思教育·河北省2024-2025学年度第一学期七年级教学质量检测二语文试题1、河北省2024-2025学年第一学期九年级教学质量检测二政治答案1、河南省2024-2025学年第一学期九年级教学质量检测二物理试题12、明思教育·河北省2024-2025学年度第一学期七年级教学质量检测二地理试题1、河北省2024-2025学年第一学期七年级教学质量检测二地理答案13.与b地相比，a地A.自转角速度更快，自转线速度相等B.自转角速度相等，自转线速度更慢C.自转角速度3、安徽省芜湖市2024-2025学年度第一学期九年级素质教育评估试卷政治试题1、安徽省芜湖市2024-2025学年度第一学期九年级素质教育评估试卷政治答案1、安徽省芜湖市2024-2025学年度第一学期九年级素质教育评估试卷历史试题
减小，烧杯中的水倒吸到集气瓶中，进入水的体积就是消耗氧气的体积，进而粗略测得空气中氧气的含量；试想能否用蜡烛、木炭代替红磷进一。用酒精灯火焰的外焰给试管内（答一点即可）。二、填空与简答题（本大题共2小题，每空1分，文字表达式2分，共27分）（4）能使澄清石灰水变浑浊的气体是（1）要防止实验室意外事故的发生。倾倒液体药品时，瓶塞要倒放在桌面上目的是（3）①实验室粗略测定空气中氧气含量的实验原理：由于红磷燃烧只消耗空气中（4分）请用下列物质的序号填空：①氧气②氮气③稀有气体①二氧化碳（2）空气中含量最多的气体是图3：铁丝在氧气中燃烧V(02)13.（7分）某兴趣小组的同学探究氧气性质的实验如图，请回答下列问题：形式的科普活动。请回答下列科普活动模拟实验中的有关问题：第二部分（非选择题共45分）反应后二氧化锰和氧化铜的化学性质都没有变化图2：镁茶在空气中燃③实验结束，进入的水没有达到的原因可能是（2）用试管加热时，液体不能超过试管容积的催化剂的催化效率，二氧化锰比氧化铜更高B.从图像中可以看出生成氧气的体积相等反应后剩余催化剂的质量，甲>乙（3）通电时发出有色光的气体是②写出红磷燃烧的文字表达式：（1）可以供给呼吸的气体是的液体加热，分析其理由是使瓶内蜡烛在空气和行实验？请说明理由：氧气中燃烧的_面A.D.11.9.实验2《氧气的实验室制取与性质》。本实验以高锰酸钾为原料，并采用排水法收集从视频中D.点燃的铁丝插入盛有氧气的集气瓶中剧烈燃烧，A.红磷在空气中燃烧，产生大量白烟B.木炭燃烧后生成一种使澄清石灰水变浑浊的气D. 收集氧气C.加热药品：先让试管底部均匀受热，再对高锰酸钾所在部位加热隐藏着危险，稍不注意就会造成安全事故，下列实验做法正确的是A.查气密性：先将导管伸入水中，再用双手紧握试管外壁固定装置：将试管口略向下倾斜，固定在铁架台上C.加热KMnOD.收集气体：导管口刚有气泡冒出就开始收集气体C下列有关加热高锰酸钾制取氧气的实验操作正确的是A.为了获得感性认识，可以触摸药品或尝药品的味道D.洒在实验台上的酒精着火应立即用湿抹布铺盖B.给试管里的液体加热时，拇指要放在短柄上C.加热试管里的液体时可以对着自己或他人8.下列关于物质燃烧的现象描述错误的是B.检查气密性看到的下列实验操作不规范的是C.硫燃烧时生成二氧化硫气体A.组装仪器火星四射B.
1、金太阳大联考南阳地区204年秋季高一年级期中适应性考试卷(25-123A)英语试题1、吉林省2024-2025学年名校调研系列卷·九年级期中测试（J）语文试题1、江苏省南京市2024届高三年级第二次模拟考试答案(物理)12、吉林省2024-2025学年名校调研系列卷·九年级第三次月考（H）历史试题浅蓝、走向深蓝的航向。“得出海军作战能力提升，具备近海作战和远洋护卫应对多种威胁的能力；根据材料"2012年，中国首艘航母辽宁'号服役，这是中国第一艘服役的航空母舰。此次服役标志着中国海军第一次有了远3、河北省秦皇岛市某校2024-2025学年第一学期期中演练九年级数学试题1、河北省秦皇岛市某校2024-2025学年第一学期期中演练九年级政治试题1、明思教育·河北省2024-2025学年度第一学期七年级教学质量检测二语文试题
2025年下学期高三9月联考·思想政治参考答案、提示及评分细则重大贡献,@正确。答案选C。误。 答案选 B。4.A①题干强调以中国式现代化全面推进强国建设、民族复兴伟业，广大青年大有可为，体现了广大青年要担当强国建设、民族复兴的历史机遇，①正确。②题干未提及全面推进强国建设要以加强党的自身建设为必然·要求，②排除。③广大青年要自觉听从党和人民召唤，坚定理想信念，奋力书写挺膺担当的青春篇章，说明广大青年应把小我融人大我，汇聚起实现中国梦的强大力量，③正确。④中国梦是国家的梦、民族的梦，也是每一个中华儿女的梦，但不是要立足伟大梦想成就伟大事业，而是要为实现伟大梦想而奋斗，④错误，排除。答案选 A。5.D①通过跨界联动等方式，拓展了“票根经济”的场景，能够有效释放游客的消费潜力，进而扩大社会总需求，该传导路径不合理，①错误。②消费者凭借交通出行，文旅活动等场景的票务凭证，在后续消费场景中享，济"模式的传导逻辑，③错误。④整合景点、演出资源，发挥文旅行业的带动作用，能够推动文旅融合发展，该传导路径合理，④正确。答案选D。是决定国家前途和命运的根本力量，@错误。答案选B。【高三思想政治试题参考答案第1页（共4页）】
