（题文）阅读材料，回答下列问题。
材料一 2014年12月26日，贵广高铁通车。该线穿过大面积喀斯特地貌区，沿线断层、河流和高峡深谷密布，桥隧比高达83％，施工难度极高。
材料二 贵广高铁线路示意图

(1)贵广高铁通车季节，贵阳多阴雨天气，试说明原因。
(2)分析贵广高铁桥隧比高的原因。
(3)说出贵广高铁的建成对广东省的意义。

将形状完全相同的不同材料做成的甲、乙两球从足够高处同时由静止释放．两球下落过程所受空气阻力大小f仅与球的速率v成正比，即f=kv（k为正的常量）．两球的v﹣t图象如图所示．则下列判断正确的是(     )

  A．释放瞬间甲球加速度较大

  B．释放瞬间甲乙两球的加速度都等于重力加速度

  C．甲球质量小于乙球

  D．甲球质量大于乙球

．（25分）阅读以下关于“海权”的材料，完成下列要求。

材料一:东汉杨孚《异物志》载：“涨海崎头，水浅而多磁石，墩外大舟，锢以铁叶，值之我拔”。三国时期万震《南州异物志》记录了从马来半岛到中国的航程，其载“东北行，极大崎头，出涨海，中浅而多磁石”。这两条史料的记述十分一致，其中所言“崎头”是我国古人对礁屿和浅滩的称呼，而“涨海”即我国古代对南海最早的称谓。“涨海崎头”指南海诸岛的礁滩。

宋代将南海诸岛列入“琼管”范围，即“千里长沙”、“万里石塘”属于当时广南西路琼州的管辖范围，这标志着南海诸岛纳入中国版图已现端倪。至明清两代，中央政府继续将南海诸岛明确列入中国版图并置于广东省琼州府万州辖下，行使了有效管辖。

二战期间，日本发动侵华战争，占领了中国大部分地区，《开罗宣言》和《波茨坦公告》及其他国际文件明确规定把被日本窃取的中国领土归还中国，这自然包括了南沙群岛。1946年12月，当时的中国政府指派高级官员赴南沙群岛接收，在岛上举行接收仪式，派兵驻守。

材料二: 中国近代的有识之士逐步认识到“兴帮[邦]张海权”的道理，孙中山说：“中国海权一日不兴，则国基一日不宁。”“争太平洋之海权，即争太平洋之门户权。人方以我为争（意为：别国以我国为争夺瓜分的对象），岂置之不知不问。”我国海疆袤延七省，苟无海军控制则海权尽失，须重戎备而固海防。盖无舰船，海防无从谈起，有舰船而无训练有素之才，无以用之，有舰械人才而无良港，则海军无驻足之所，一切皆备而无民生之政府，则必导甲午之覆辙。海事既备，当以中国人工用船荒之时建船舶、兴商务，勾连世界，亦可得鱼盐之利，可围海造田、潮汐发电。

                                            ——摘编自杨金森范中义《中国海防史》

材料三: 近30年来发生在中国周边海域的一系列事件，都使海洋、海权等问题在中国社会的热度不断升温。……调查发现，有79%的受调查者认为海权就是中国依法享有的海洋权益，包括在领海以及专属经济区内航海、养殖、捕捞、开采油气和矿产资源的排它性的权力，而仅有15．9%的受调查者认为海权是控制海洋的权力。恰恰相反，西方社会则普遍认为海权无非是控制海洋的权力。

——摘自《环球》杂志《中国精英海权意识的嬗变》

（1）根据材料一，说明中国对南海诸岛及其附近海域拥有无可争辩的主权。（6分）

（2）依据材料二概括孙中山的海权思想（不得照抄原文。）并结合所学知识分析其原因。（12分）

（3）据材料三，概要指出中西方海权观的主要差异是什么？据此你认为维护中国海洋权益的关键是什么？（7分）

空间存在匀强电场，有一电荷量、质量的粒子从点以速率射入电场，运动到点时速率为。现有另一电荷量、质量的粒子以速率仍从点射入该电场，运动到点时速率为。若忽略重力的影响，则     （     ）

       A．在、、三点中，点电势最高

       B．在、、三点中，点电势最高

       C．间的电势差比间的电势差大

       D．间的电势差比间的电势差小

The city of Los Angeles is finally getting serious about retrofitting(翻修) the soft wood frame apartment buildings and the weak concrete ones that are at risk of collapsing during a substantial earthquake. A concrete building without adequate steel reinforcement can crumble to the ground, as some did in the 1971 Sylmar earthquake, killing dozens.

The first step is to take a list of the 29,000 apartment buildings that were built before 1978, when the building code was changed to require stronger wood frame and concrete buildings. The second step will be the analysis of those buildings by structural experts to see if they should be  retrofitted, which needs essential professionalism. Then comes the stage to decide who pays for the work that needs to be done, Landlords? Renters? Taxpayers?  The step posed the biggest obstacle to all parties involved. 

Actually Under L.A.'s rent control law, property owners can pass on 100% of the cost of ‘essential’ retrofitting work to renters. Some favor this pass-through move, arguing that many mom-and-pop landlords of small buildings are as cash-strapped as one can imagine, if not more so.

However, the reality is that, like many landlords, the insolvency of most renters will finally make the retrofitting an empty talk. Besides, the cost of retrofitting should not fall on any one group as this work is done to prevent people from being killed in earthquakes. Protecting buildings serves the interests of renters, property owners and the city as a whole, which qualifies it as a matter of public safety issue so that L.A. government needs to find ways to shoulder some burden of the cost.

It has been decided by the city government that the government will get involved, trying to find ways to reduce costs for landlords for the retrofitting projects, and the government is establishing a law to create a tax reduction for retrofitting for landlords. It's not clear at this point how much tax the state could afford to give up, or how much tax cut owners can get.  Some even say that the actual financial assistance landlords can get is far less than is expected.  However, what it’s known definitely now is that Los Angeles must not allow retrofitting to be put off although the money issue poses a big problem. The bottom line is the human life rather than money.

74. According to the passage, which issue is the most essential in deciding the future of the city’s retrofitting project?

   A. Having all the parties involved aware of the importance of retrofitting.

   B. Making a list of all the buildings that were built before a certain date.

   C. Deciding professionally on whether the listed buildings need retrofitting.

   D. Working out adequate ways to provide financial support for retrofitting.

75. According to the passage, the underlined word insolvency is closest in meaning to ______.

   A. not having enough money to pay debts

   B. poor relationship with landlords

   C. unwillingness to participate

   D. unfair treatment received

76. Which of the following is implied about the retrofitting project?

   A. Most L.A. apartments are of Soft wood frame or of weak concrete.

   B. According to L.A. rent law, landlords and renters share the cost for retrofit work. 

   C. According to government decision, owners will mainly be responsible for the retrofit.

   D. Government will pay mainly for the retrofitting work as it relates with people’s life.

77. What is the main idea of the passage?

   A. The likelihood of weak apartment falling in big earthquakes.

   B. The background of LA apartment retrofit and its financial solution.

   C. The argument between landlords, renters and governments over money issues.

    D. The importance of LA government’s involvement in life-saving projects.

下列实验操作能达到实验目的的是

	实验目的	实验操作
A	鉴别苯和溴乙烷	取少量苯和溴乙烷，分别加入水
B	除去二氧化碳中的氯化氢	将气体通入碳酸钠溶液中
C	比较氯和硅的非金属性强弱	将盐酸滴入Na2SiO3溶液中
D	验证在酸作用下，蔗糖水解能否生成葡萄糖	取水解后的液体，加入新制的氢氧化铜加热

A. A                   B. B                   C. C                   D. D

足量铜与一定量浓硝酸反应，得到硝酸铜溶液和NO₂、NO的混合气体，这些气体与1.68 L O₂(标准状况)混合后通入水中，所有气体完全被水吸收生成硝酸。若向所得硝酸铜溶液中加入5 mol·L^－1 NaOH溶液至Cu^2＋恰好完全沉淀，则消耗NaOH溶液的体积是(　　)

A．60 mL   B．45 mL   C．30 mL  D．15 mL

人类红绿色盲的基因位于X染色体上、秃顶的基因位于常染色体上，结合下表信息可预测，图中II—3和II—4所生子女是（      ）

	BB	Bb	bb
男	非秃顶	秃顶	秃顶
女	非秃顶	非秃顶	秃顶

A.非秃顶色盲儿子的概率为1/16       B.非秃顶色盲女儿的概率为1/4

C.秃顶色盲儿子的概率为1/4           D.秃顶色盲女儿的概率为1/8

教育承载着为国家培养人才的重任，教育指导思想往往反映了时代的要求。下列建国后不同时期的教育指导思想中，为适应进入全面建设社会主义时期需要而提出的是

A．“教育的目的，是培养有社会主义觉悟的有文化的劳动者”

B．“紧密结合阶级斗争和路线斗争的实际组织教学”

C．“教育要面向现代化，面向世界，面向未来”

D．“为工农服务，为生产建设服务，这就是当前实行新民主主义教育的中心方针”

等位基因（A、a）位于某种昆虫的常染色体上，该种昆虫的一个数量非常大的种群在进 化过程中，a 基因的频率与基因型频率之间的关系如图。以下叙述正确的是（ ）

A.Ⅰ、Ⅱ、Ⅲ分别代表 AA、Aa、aa 的频率
B.A 基因的频率为 0.25 时，Aa 的基因型频率为 0.75
C.a 基因控制的性状表现类型更适应环境
D.生物进化的实质是种群基因型频率发生定向改变

为测定某有机化合物A的结构，进行如下实验。

【分子式的确定】

(1)将有机物A置于氧气流中充分燃烧，实验测得：生成5.4 g H₂O和8.8 g CO₂，消耗氧气6.72 L(标准状况下)，则该物质中各元素的原子个数比是____________________。

(2)质谱仪测定该有机化合物的相对分子质量为46，则该物质的分子式是________。

(3)根据价键理论，预测A的可能结构并写出其结构简式____________________。

[结构式的确定]

(4)¹H核磁共振谱能对有机物分子中不同位置的氢原子给出不同的峰值(信号)，根据峰值(信号)可以确定分子中氢原子的种类和数目。例如：甲基氯甲基醚(Cl—CH₂—O—CH₃)有两种氢原子(如图1)。经测定，有机物A的¹H核磁共振谱示意图如图2所示，则A的结构简式为________。

图1　　　　　　　　图2

【性质实验】(5)A在一定条件下脱水可生成B，B可合成包装塑料C，请写出B转化为C的化学方程式：

_____________________________________________________。

(6)体育比赛中当运动员肌肉扭伤时，队医随即用氯乙烷(沸点为12.27 ℃)对受伤部位进行局部冷冻麻醉。请用B选择合适的方法制备氯乙烷，要求原子利用率为100%，请写出制备反应的化学方程式：

________________________________________________________________。

知函数f（x）=ax²﹣2x+lnx（a≠0，a∈R）．

（1）判断函数 f （x）的单调性；

（2）若函数 f （x）有两个极值点x₁，x₂，求证：f（x₁）+f（x₂）＜﹣3．

　

在图示的电路中，闭合开关后，当滑动变阻器的滑动触头P从最上端逐渐滑向最下端的过程中，电压表V的读数变化量为ΔU，电流表A₂的读数变化量为ΔI₂（电表均视为理想电表）。则

A．电压表V的读数先变小后变大

B．电流表A₁的读数先变大后变小

C．电流表A₂的读数变大

D．ΔU与ΔI₂的比值为定值

研究者破坏某原核细胞的DNA后，再“注入”人造DNA，得到具有生命特征的“人造生命”．下列有关“人造生命”的判断不正确的是（）

      A． 含量最多的化合物是水 B．  遗传信息储存在RNA中

      C．人造DNA控制合成蛋白质   D． 具有能生长、繁殖的特征

某研究性学习小组采用盆栽实验，探究土壤干旱对某种植物叶片光合速率的影响。实验开始时土壤水分充足，然后实验组停止浇水，对照组土壤水分条件保持适宜，实验结果如图所示。下列相关分析正确的是

A．叶片光合速率随干旱时间延长而呈下降趋势可能是由CO₂固定减少引起的

B．叶片光合速率下降和叶片叶绿素含量下降是同步的

C．实验2～4 d，光合速率下降是由叶片叶绿素含量下降引起的

D．实验2～4 d，光合速率下降不可能是由叶片内二氧化碳浓度下降引起的

    Every Australian child is brought up on Vegemite(维吉米特黑酱)!Yes, this dark colored food paste made from yeast extract(酵母膏)is put on fresh bread and toast as a snack, breakfast, lunch on the run or when there's basically nothing else left in the house to eat. It takes time to adapt to it for those not used to it. Simply watch overseas visitors make faces when tasting it for the first time found in every indigenous Australian home! In fact, it is considered a national food and cultural sign.

    Vegemite has an interesting history. More than ninety years ago, a leading Australian food technologist was given the challenge of creating a food item from a by-product of the beer manufacturing process. This by-product was developed into a pure vegetable extract spread for use on bread and toast. It has since found its way into many Australian homes.

    Before World War II it was confirmed by the British Medical Association for its medicinal benefits as a nutritionally balanced food for patients. It became very important during World War II. As a result of the heavy demand by the armed forces, the supplies to civilians were rationed(限量)with the following message given by the government：Vegemite fights with the men up north! If you are one of those who don't need Vegemite medicinally, then thousands of the injured are asking you to deny yourself of it for the time being. After the war, with many babies born, Vegemite was confirmed as a necessary source of Vitamin B1, B2 for babies.

29．What does the underlined word “indigenous” in Paragraph 1 mean?

A．Rich.    B．Native.    C．Remote.    D．New.

30．What's the purpose of the message given by the government?

A．To encourage Australians to fight for their nation.

B．To tell people Vegemite has high nutritional value.

C．To suggest that people leave Vegemite to the army.

D．To inform Vegemite has medical functions.

31．The author is trying to show us the fact that Vegemite ________.

A．has been a part of Australian history

B．is a kind of popular food for babies only

C．is popular in every English-speaking country

D．has become a favorite food for overseas visitors

受疫情影响,各地实行部分企业免征纳税人增值税和其他费用;个体工商户按单位参保养老失业、工伤保险,参照中小微企业享受减免;落实除高耗能行业外工商业电价阶段性降低5%政策。上述举措对当前经济社会发展的影响路径是（ ）
①缓解企业经营压力②完善社会保障制度③增加市场消费需求
④助力企业复工复产⑤促进经济平稳运行⑥降低制度性交易成本
A.①→④→⑤→② B.⑥→②→③→⑤
C.②→⑥→④→③ D.⑥→①→④→⑤

已知函数, , 两个函数图象的公切线恰为3条, 则实数的取值范围为               . 

下图为世界某海域。由于洋流的影响导致各处水温有差异。完成下面小题。

【1】与图示海区洋流流向有关的风向及主要来源地是
A.东南风 夏威夷高压 B.东北风 亚洲高压
C.西北风 副热带高压 D.西南风 印度低压
【2】图中四地在该季节发生的地理现象，叙述正确的
A.①地处于全年的气温最高季节 B.②地正值秋风瑟瑟，稻花飘香
C.③地地下水位为一年中较高位 D.④地沿岸海域的鱼类密度较大