三阶行列式第2行第1列元素的代数余子式为10，则k= ．

请将下面这则新闻压缩成一句话新闻，不超过25个字。 

（北京6月27日电）(记者牛梦笛)中央广播电视总台日前成功实现了我国首次8K超高清内容的5G远程传输，并为参加2019世界移动大会的嘉宾现场呈现出极致流畅的传输速度以及色彩鲜艳、纤毫毕现的画质体验。

据悉，此次直播电视信号的传输测试，是由中央广播电视总台联合中国移动、中国联通、华为公司、中国超高清产业联盟以及北京数码视讯公司共同完成。此次测试在中央广播电视总台北京光华路办公区架设了8K超高清摄像机，利用运营商提供的5G超高速网络，结合信号传输及视音频编解码设备，将电视节目信号传送到了位于上海展示现场的8K显示终端，整个过程实时直播，实现了最高在320Mb/s速率下的8K视频传输。

这次测试实践充分验证了5G网络在传输方面的优势，为整个超高清电视的应用提供了极好的技术支撑。

设 ， ，则方程 的解集为（    ）

100mL物质的量浓度为b ，溶质的质量分数为a%的稀盐酸，有关此盐酸的说法正确的是（   ）

由9个正数组成的矩阵 中，每行中的三个数成等差数列，且a₁₁+a₁₂+a₁₃ ， a₂₁+a₂₂+a₂₃ ， a₃₁+a₃₂+a₃₃成等比数列，给出下列判断：①第2列a₁₂ ， a₂₂ ， a₃₂必成等比数列；②第1列a₁₁ ， a₂₁ ， a₃₁一定成等比数列；③a₁₂+a₃₂≥a₂₁+a₂₃；④若9个数之和等于9，则a₂₂≥1．其中正确的个数有（　　）

下面文段有四处语言表达的问题，请指出有问题句子的序号并修改，使语言表达准确流畅。

①2020年初春，一场疫情不期而至。②截至2月底为止，我市已有6名医护人员感染新冠病毒，③市长惭愧地说，我们领导在这次疫情中没尽到责任，④我们愿意革职，⑤希望大家齐心协力抗疫情，完成这次战疫的最后胜利。⑥3月15日我市全面疫情防控阻击战取得胜利，确诊病例清零。⑦白衣天使完成使命，胜利归来。

下列句子中不包含词类活用的一项是（    ）

他到底是怎样说服父亲戒烟的?

将19.2 g Cu溶于100 mL浓度均为1 mol·L^－1的HNO₃和H₂SO₄的混合溶液中，若产生的气体为NO，则产生的NO在标准状况下的体积为(   )

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。
    More and more foreigners like to come to China. Last Friday our school was invited a foreign teacher in our city give a class to the students of Senior Grade Two. We found his class interested. I learned a lot from him. The teacher had a free talk to us with easy English . He spoke slow so that we could understand him well. Sometimes he repeated what we don't understand. My classmates were all active in the class. To his joy, I understood everything the teacher said. And I was able to ask question in English. This class encouraged me very much. I'm sure that until we keep on practising, it will be easy for us to learn speaking English well.

文中共有10处语言错误。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（\）。

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）、每处错误极其修改均仅限一词；

      2）、只允许修改10处，多者（从第11处起）不计分。

    I'm a student from Chongqing, China. I am write to keep you informing of something about the severe situation that finless porpoises, a kind of rare and lovely animal, are facing with presently.

    It's because of human activities that finless porpoises are endangered. It's terrible that there are merely less than 1,000 finless porpoises live in China. However, it's high time that immediate measures must be taken. Don't you think so? If possible, how I hope you can help us by funding your project aiming at protecting finless porpoises! Under your financial aid, I am convinced fewer finless porpoises will survive. I would appreciate greatly if you could consider my application.

    Looking forward to your early reply.

文言文阅读

蒙恬者，其先齐人也。恬大父蒙骜，自齐事秦昭王。庄襄王二年，攻赵，取三十七城。始皇七年，卒。骜子曰武，武子曰恬。始皇二十三年，蒙武为秦裨将军，与王翦攻楚，大破之，杀项燕。蒙恬弟毅。始皇二十六年，蒙恬因家世得为秦将，攻齐，大破之，拜为内史。秦已并天下，乃使蒙恬将三十万众北逐戎狄 ， 收河南。筑长城因地形用制险塞起临洮至辽延袤万馀里于是渡河据阳山逶蛇而北暴师于外十馀年，居上郡。是时蒙恬威振匈奴。始皇甚尊宠蒙氏，信任贤之。恬任外事而毅常为内谋，名为忠信，故虽诸将相莫敢与之争焉。

始皇欲游天下，三十七年冬，行出游会稽，至沙丘崩 ， 秘之，群臣莫知。是时丞相李斯、公子胡玄、中车府今赵高常从。高雅得幸于胡亥，欲立之，乃与李斯阴谋立为太子，遣使以罪赐公子扶苏、蒙恬死。扶苏已死，蒙恬疑而复请之。胡亥已闻扶苏死，即欲释蒙恬。赵高恐蒙氏复贵而用事，怨之。赵高因为胡亥忠计，欲以灭蒙氏，乃言曰：“臣闻先帝欲举贤立太子久矣，而毅谏曰‘不可’．以臣愚意，不若诛之。”胡亥听而系蒙毅于代。前已囚蒙恬于阳周。丧至成阳，已葬，太子立为二世皇帝，而赵高亲近，日夜毁恶蒙恬，求其罪过，举劾之。子婴进谏曰：“诛杀忠臣而立无节行之人，是内使群臣不相信而外使斗士之意离也，臣窃以为不可。”胡亥不听。而遣御史之代，使者知胡亥之意，不听蒙毅之言，遂杀之。二世又遣使者之阳周，恬曰：“臣将兵三十馀万，身虽囚系，其势足以倍畔，然自知必死而守义者，不敢辱先人之教，以不忘先主也。”使者曰：“臣受诏行法于将军，不敢以将军言闻于上也。”蒙恬喟然太息曰：“我何罪于天，无过而死乎？”良久，徐曰：“恬罪固当死矣。起临洮属之辽东，城堑万馀里，此其中不能无绝地脉哉？此乃恬之罪也。”乃吞药自杀。

太史公曰：吾适北边，自直道归，行观蒙恬所为秦筑长城亭障，堑山堙谷，通直道，固轻百姓力矣。夫秦之初灭诸侯，天下之心未定，痍伤者未瘳，而恬为名将，不以此时强谏，振百姓之急，养老存孤，务修众庶之和，而阿意兴功，此其兄弟遇诛，不亦宜乎!何乃罪地脉哉？

（节选自《史记•蒙恬列传》）

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。

    Sam went to the cinema the other night. Entered the cinema, he thought of taking off his coat. But the cinema was very cold and he has to keep his coat on. As there weren't much space between the rows, his legs began to ache shortly after he took up his seat. Worse still, they found it difficult to breath easily. Looking around, he saw a lot of people smoking. At last the film started. That made him angry was that the person in front was wearing so big hat that he could hardly see the screen. To top it all, people all around him either told jokes nor laughed loudly. However, Sam missed most of the dialogue.

阅读下面的文字，完成问题。

材料一：

2020年9月14日至20日是国家网络安全宣传周。共青团中央维护青少年权益部、中国互联网络信息中心前不久联合发布的《2019年全国未成年人互联网使用情况研究报告》显示，32.9%的小学生网民在学龄前就开始使用互联网。

有教师在教学中发现，因过度沉浸社交媒体使用，青少年中不同程度地出现手机依赖、饭圈追星、亲子关系紧张、厌学等现象。此外，中国社科院的调查显示，青少年应对网络风险的能力相对较弱，45%的青少年在注册账号时不太关注用户协议，对自己的权利和义务不太了解。

专家表示，与媒介技术的发展和带来的影响相比，青少年对媒介及信息的认识和辨别能力还存在很多不足，整体来看，我国青少年的媒介素养急切需要提升。当前正处于学校“复学”阶段，提高青少年的媒介素养及“信息生存”能力变得更加紧迫。

（摘编自《中国教育报》）

材料二：

青少年网络行为的引导和心理建设除了需要教育机构、政府以及社会群体等公共力量的相互配合外，各企业平台更要承担自己的责任，由此形成良性的、可循环的协作机制。

对于各企业平台而言，要降低青少年的网络参与风险，必须充分挖掘自身平台海量数据的优势、发挥青少年数据分析红利，加强对青少年网络使用心理、态度、行为倾向的研究。基于平台细颗粒度数据挖掘与分析，对青少年进行多维度、分层次、趋势性研究。根据具体内容展开具体分析，针对具体问题提出具体对策。

企业有责任加强自身网络空间内的信息安全的管控与动态调整。同时，配合政府政策，制定和修改平台内的网络安全规范，及时向政府相关部门进行问题反馈，推动相关法律法规建设。监管层面，企业作为网络的主要负责主体，要充当好把关人角色。除了约束机制外，平台也需要相应的鼓励性措施，对面向青少年的健康网络节目进行奖励，共同营造良好的网络使用环境。

大数据的发展促进了网络信息共享的同时，也增加了青少年接触不良网络内容的风险，故而，通过加强对于网络协议的控制，开发针对青少年的网络加密技术，鼓励企业在开发产品时，设立专为青少年使用的模式和平台，保护青少年群体权益；在信息筛选方面，通过自然语言处理等技术对负面内容进行智能语义聚合，在进行人工复查之前就能够通过工具进行初步的筛选；定期对网络漏洞进行扫描，对主要网站或者是青少年聚集的网络地带进行风险评估，确保网络系统在最优条件下运行；网络平台通过与学校或者是家庭进行合作，推出网络安全服务，如访问控制、通信伙伴认证等间接管理青少年对网络的使用。与此同时，除了限制不良信息对青少年的冲击之外，青少年自身的信息和隐私保护也应引起重视，依据大教据的云系统等，建立并储存青少年相关的信息数据库，当青少年遭遇网络使用危险之时，该系统能及时响应并作出急救反馈。

（摘编自《中国青年报·青少年互联网平台参与风险研究报告综述》）

材料三：

（摘编自《中国青年报·青少年互联网平台参与风险研究报告综述》

完形填空

阅读下面短文，掌握其大意，然后从1—20各题所给的四个选项（A、B、C和D）中，选出最佳选项。

    I was required to read one of Bernie Siegel's books in college and was hooked on his positivity from that moment on．The stories of his unconventional1 and the exceptional patients he wrote about were so2 to me and had such a big3 on how I saw life from then on．

    Who knew that so many years later I would look to Dr．Bernie and his CDs again to4 my own Cancer experience ？

    I'm an ambitious5 , and when I started going through chemo( 化疗 )，even though I'm a very6 person, I lost my drive to write．I was just too tired and not in the7 ．One day, while waiting to go in for 8, I had one of Dr．Bernie's books in hand．Another patient 9 what I was reading and struck up a conversation with me10 he had one of his books with me as well．It11that among other things, he was an eighty-year-old writer．He was12a published author, and he was currently13on a new book．

    We would see each other at various times and14friends．Sometimes he wore a duck hat, and I would  tell myself, he was definitely a ( n ) 15 of Dr．Berline．He really put a16 on my face．He unfortunately17last year due to his cancer,18 he left a deep impression on me and gave me the19 to pick up my pen again．I20 to myself, “If he can do it, then so can I．”

Something suspicious was found after the room was sought .

下列对这首诗的理解和赏析，不恰当的一项是（  ）

纪村事        [唐]韦庄

绿蔓映双扉，循墙一径微。雨多庭果烂，稻熟渚禽肥。

酿酒迎新社，遥砧送暮晖。数声牛上笛，何处饷田^注归。

[注] 饷田：到田间送饭。

阅读理解

    Nuclear power's danger to health, safety, and even life itself can be summed up in one word: radiation.

    Nuclear radiation has a certain mystery about it, partly because it cannot be detected by human senses. It can't be seen or heard, or touched or tasted, even though it may be all around us. There are other things like that. For example, radio waves are all around us but we can't detect them, sense them, without a radio receiver. Similarly, we can't sense radioactivity without a radiation detector. But unlike common radio waves, nuclear radiation is not harmless to human beings and other living things.

    At very high levels, radiation can kill an animal or human being immediately by killing masses of cells in vital organs. But even the lowest levels can do serious damage. There is no levels of radiation that is completely safe. If the radiation does not hit anything important, the damage may not be serious. This is the case when only a few cells are hit, and if they are killed immediately. Your body will replace the dead cells with healthy ones. But if the few cells are only damaged, and if they reproduce themselves, you may be in trouble. They can grow into cancer. Sometimes this does not show up for many years.

    This is another reason for some of the mystery about nuclear radiation. Serious damage can be done without the victim being aware at the time that damage has occurred. A person can be irradiated(辐射)and feel fine, then die for cancer five, ten, or twenty years later as a result. Or a child can be born weak as a result of radiation absorbed by its grandparents.

    Radiation can hurt us. We must know the truth.

The current (趋势) is towards more part time employment.

阅读理解

The Uniqueness of Finger-prints (指纹的唯一性)

    Every human being has a unique① arrangement of the skin on his fingers and this arrangement is unchangeable. Scientists and experts have proved the uniqueness of finger-prints and discovered that no exactly similar pattern is passed on from parents to children, though nobody knows why this is the case.

    The ridge structure on a person's fingers does not change with growth and is not affected by surface injuries. Burns, cuts and other damage to the outer part of the skin will be replaced in time by new one, which bears a reproduction of the original② pattern. It is only when the inner skin is injured that the arrangement will be destroyed. Some criminals make use of this fact to remove their own finger-prints but this is a dangerous and rare step to take.

    Finger-prints can be made very easily with printer's ink. They can by recorded easily. With special methods, identification③ can be achieved successfully within a short time. Because of the simplicity and economy of this system, finger-prints have often been used as a method of solving criminal case. A suspected man may deny a charge but this may be in vain. His finger-prints can prove who he is even if his appearance has been changed by age or accident.

    When a suspect leaves finger-prints behind at the scene of a crime, they are difficult to detect with the naked eye. Special techniques are used to "develop" them. Some of the marks found are incomplete but identification is possible if a print of a quarter of an inch square can be obtained.

Choose the best answers according to the above.