2.某小组有20名射手,其中1,2,3,4级射手分别为2,6,9,3名.又若选1,2,3,4级射手参加比赛,则在比赛中射中目标的概率分别为0.85,0.64,0.45,0.32,今随机选一人参加比赛,则该小组比赛中射中目标的概率为________. 【解析】设B表示“该小组比赛中射中目标”,Ai(i=1,2,3,4)表示“选i级射手参加比赛”,则P(B)= P(Ai)P(B|Ai)= 2/20×0.85+ 6/20 ×0.64+ 9/20×0.45+ 3/20×0.32=0.527 5.答案:0.527 53.两批相同的产品各有12件和10件,每批产品中各有1件废品,现在先从第1批产品中任取1件放入第2批中,然后从第2批中任取1件,则取到废品的概率为________. 【解析】设A表示“取到废品”,B表示“从第1批中取到废品”,有P(B)= 112,P(A|B)= 2/11 ,P(A| )= 1/11所以P(A)=P(B)P(A|B)+P( )P(A| )4.有一批同一型号的产品,已知其中由一厂生产的占 30%, 二厂生产的占 50% , 三厂生产的占 20%, 又知这三个厂的产品次品率分别为2% , 1%, 1%,问从这批产品中任取一件是次品的概率是多少?
(2)方法一:第一次取到一件不合格品,还剩下99件产品,其中有4件不合格品,95件合格品,于是第二次又取到不合格品的概率为4/99,由于这是一个条件概率,所以P(B|A)=4/99.方法二:根据条件概率的定义,先求出事件A,B同时发生的概率P(AB)=(C_5^2)/(C_100^2 )=1/495,所以P(B|A)=(P"(" AB")" )/(P"(" A")" )=(1/495)/(5/100)=4/99.6.在某次考试中,要从20道题中随机地抽出6道题,若考生至少答对其中的4道题即可通过;若至少答对其中5道题就获得优秀.已知某考生能答对其中10道题,并且知道他在这次考试中已经通过,求他获得优秀成绩的概率.解:设事件A为“该考生6道题全答对”,事件B为“该考生答对了其中5道题而另一道答错”,事件C为“该考生答对了其中4道题而另2道题答错”,事件D为“该考生在这次考试中通过”,事件E为“该考生在这次考试中获得优秀”,则A,B,C两两互斥,且D=A∪B∪C,E=A∪B,由古典概型的概率公式及加法公式可知P(D)=P(A∪B∪C)=P(A)+P(B)+P(C)=(C_10^6)/(C_20^6 )+(C_10^5 C_10^1)/(C_20^6 )+(C_10^4 C_10^2)/(C_20^6 )=(12" " 180)/(C_20^6 ),P(E|D)=P(A∪B|D)=P(A|D)+P(B|D)=(P"(" A")" )/(P"(" D")" )+(P"(" B")" )/(P"(" D")" )=(210/(C_20^6 ))/((12" " 180)/(C_20^6 ))+((2" " 520)/(C_20^6 ))/((12" " 180)/(C_20^6 ))=13/58,即所求概率为13/58.
3.某县农民月均收入服从N(500,202)的正态分布,则此县农民月均收入在500元到520元间人数的百分比约为 . 解析:因为月收入服从正态分布N(500,202),所以μ=500,σ=20,μ-σ=480,μ+σ=520.所以月均收入在[480,520]范围内的概率为0.683.由图像的对称性可知,此县农民月均收入在500到520元间人数的百分比约为34.15%.答案:34.15%4.某种零件的尺寸ξ(单位:cm)服从正态分布N(3,12),则不属于区间[1,5]这个尺寸范围的零件数约占总数的 . 解析:零件尺寸属于区间[μ-2σ,μ+2σ],即零件尺寸在[1,5]内取值的概率约为95.4%,故零件尺寸不属于区间[1,5]内的概率为1-95.4%=4.6%.答案:4.6%5. 设在一次数学考试中,某班学生的分数X~N(110,202),且知试卷满分150分,这个班的学生共54人,求这个班在这次数学考试中及格(即90分及90分以上)的人数和130分以上的人数.解:μ=110,σ=20,P(X≥90)=P(X-110≥-20)=P(X-μ≥-σ),∵P(X-μσ)≈2P(X-μ130)=P(X-110>20)=P(X-μ>σ),∴P(X-μσ)≈0.683+2P(X-μ>σ)=1,∴P(X-μ>σ)=0.158 5,即P(X>130)=0.158 5.∴54×0.158 5≈9(人),即130分以上的人数约为9人.
鉴于:1、甲方为 活动的唯一组织及承办单位。2、乙方为从事移动音视频服务的专业公司,旗下拥有 直播平台,具备承办本合同约定的相关事项的能力及资源。3、根据《中华人民共和国合同法》及相关法律法规的规定,甲乙双方本着互利共赢、精诚合作的原则和精神,就双方合作开展 大赛线上直播活动等相关事宜,在湖南省长沙市达成并签订如下协议,以兹共同遵守:一、合作单位二、合作期限本合同约定的合作期限为:自20xx年9月2日起至20xx年10月30日止,如因本协议约定的活动及后续事项需要延长合作期限的,则合作期限自动顺延至事项处理完毕。三、双方的权利与义务(一)甲方的权利和义务1、对本次 大赛全过程负责总体组织协调,做好各环节的衔接工作,联系其他主办方,按照分工做好分内工作;2、负责本次 大赛的整体策划和赛事、赛程设计安排工作;3、负责本次 大赛的前期报名组织工作,负责协调其他主办方,做好海选、初赛、复赛、决赛环节的评委邀请、场地选择、选手组织、宣传推广等工作,并对于 线上海选及线下现场直播工作给予必要的协助;4、负责 总决赛的评委邀请、奖品制作、总决赛舞台布景等工作;
托运单位: 电器厂 联系人: 电话: 地址: 市 路 号 货物名称 包装式样 件数 每件体积(立方米)长×阔×宽 重量(公斤) 托运总吨位每件 最重件 实重吨 车辆吨需要车辆数:4吨车一辆 需要车种: 起运地: 路 号 到达地: 路 号发货单位: 厂 收货单位: 厂 运到日期:托运日起 天内 委托注意事项: 1.雨天不运; 2.非危险品; 3.有自备机具装车; 4.有自备机具卸车; 5.发货单位星期二厂休; 6.收货单位星期三厂休。
一、出租情况 1-1 甲方出租给乙方的的主要情况如下: 座 落:上海市_____区____路___号(弄)____室(以下简称该房屋)。 建筑面积:________平方米。 土地用途:__________。 结 构:__________。 楼 层:本房屋所在建筑共____层,本房屋位于第__层,有/无电梯。 装修情况:精装修房配家具和电器(清单见后)。 (简装修不配家具电器) (毛坯房) 该房屋的房产证及平面图复印件见本合同附件(一)。 甲方已向乙方出示原件,乙方确认复印件与原件一致。房地产权证证书编号:________________。 1-2 甲方作为该房屋的房地产权人与乙方建立租赁关系。签订本合同前,甲方已告诉乙方该房屋未设定抵押。甲方作为该房屋的房地产权人与乙方建立租赁关系。签订本合同前,甲方已告诉乙方该房屋已设定抵押(按揭)。甲方保证本租赁事宜已经抵押权人同意。若因抵押原因需要处分本房屋,双方同意按本合同第九部分解除本合同的条件的有关内容处理。1—3 本房屋的产权共有人包括:_____________。甲方保证所有产权共有人均同意将该房屋出租给乙方使用,并与甲方共同在本合同上签字确认,出租的房屋没有权属纠纷。(产权共有人以授权的方式委托甲方签字,甲方保证授权委托书真实有效,并承担相应的法律责任。)1-4 该房屋的公用或合用部位的使用范围、条件和要求;现有装修、附属设施、设备状况和甲方同意乙方自行装修和增设附属设施的内容、标准及需约定的有关事宜,由甲、乙双方分别在本合同附件(二)、(三)中加以列明。甲、乙双方同意该附件作为甲方向乙方交付该房屋和本合同终止时乙方向甲方返还该房屋的验收依据。
双方同意签订本公寓房预订合同,并订立条款如下:1.乙方向甲方预订上海遵义南路88号“协泰中心”大厦内 楼 室公寓房 套,建筑面积(指建筑设计图计算)共计 平方米,房价共计 美元(附房屋平面图一份)。2.双方同意公寓房屋价格以美元为计算货币单位。乙方以付汇方式汇入甲方指定的银行帐户内,汇款费用由乙方自理。3.乙方同意在预计合同签署后的十四天内预付房价的百分之 ( %)即 美元,在预计房屋交付之日,买卖契约签署后的十四天内付清剩余的房价的百分之 ( %)。4.若乙方在第三款所规定的付款日期内不能付讫应付房价款,甲方将向乙方按日收取滞纳金,滞纳金以应付房价款的千分之 ( ‰)计算。5.“协泰中心”是建造在上海虹桥经济技术开发区28-3C地块上的大厦,该土地是经上海市土地局批准,甲方以 万美元中标,获得50年有偿使用权(截止公元 年 月 日),因此,乙方购入的公寓房连同相应的_____平方米的土地使用权一并购入。房产权和土地使用权期限到公元 年 月 日止。
甲、乙双方在平等、自愿、协商一致的基础上,就乙方购买甲方预售的《 》商品房事宜,订立本合同。第一条甲方通过土地使用权出让/转让/划拨方式取得 区/县 地块土地使用权,并依法进行了土地使用权登记取得房地产权证,证书号为: , 土地面积为: ,土地用途为“ . 甲方经批准,在该地块上投资建造《 》(暂定名/现定名)商品房,主体寻址建筑 结构为_________结构; 建筑物地上层数为_________层,地下层数为______层。上述商品房已具备《上海市房地产转让办法》规定的预售条件,___________________局已批准上市预售 (预售许可证编号:___________________)。第二条乙方向甲方购买___________________路___________________《___________________》___幢 (号___层__室(以下简称该房屋),政府批准的规划用途为__________.据甲方暂测该房屋建筑面积为_________平方米,其中套内建筑面积为_________平方米、公用分摊建筑面积为___平方米。该房屋建筑层高为_____米。该房屋建筑设计及平面图见本合同附件二;该房屋建筑结构、装修及设备标准见本合同附件三;该房屋相关情况说明 (抵押关系、租赁关系、相邻关系及小区平面布局)见本合同附件四;该房屋《前期物业管理且务合同》、《使用公约》或有关承诺书见本合同附件五。
双方根据《上海市优惠价房出售管理办法》的有关规定,签订本合同。1.甲方同意将坐落在上海市 区(县) 街道(镇) 路 (新村弄) 支弄 号 室计建筑面积 平方米的房屋以优惠价出售给乙方。2.上开房屋按住房综合造价的 % 年每平方米建筑面积 元计价,另计房屋地段、层次、朝向、设施因素计算,每平方米建筑面积售价 元,共计售价(大写) 元。3.乙方在合同签定时交纳定金叁百元整。4.乙方在合同签订后30天内一次付清购房款,甲方给予 %优惠,乙方实付价款(大写) 元。5.乙方要求分期付款,必须征得甲方同意。首期付款占应付款 %,计(大写) 元。余额计(大写) 元,分 年付清,月利率 ‰,余额款本息共计(大写) ,每月月底前交付(大写) 元,最后在 年 月底前全部付清。合同签订后30天内交付首期购房款。
(1)导入:拿出锻炼身体的运动图片提问“小朋友们,你们看一看今天老师手里面拿的是什么东西呢?有谁知道图片里出现了哪些画面呢?”使幼儿积极参与到活动中来,引导幼儿谈话。正如《纲要》中指出:发展幼儿的语言关键是创设一个能使幼儿想说、敢说、喜欢积极主动的环境,而这样的环境就需要老师的多多提问。充分发挥幼儿的思维能力。更好的理解儿歌的重点《天天锻炼身体好》。(2)欣赏歌曲:欣赏歌曲,帮助幼儿理解歌词内容。教师播放儿歌要求幼儿认真倾听。然后根据歌词提出相关的问题如“刚才我们一起听过了歌曲小朋友们有没有发现里面有什么感兴趣的东西呢?他出现了哪些词语。
2. let the Ss complete the forms paragraph by paragraph. Purpose here is to help Ss to get the habit of reading a passage as a whole, and pay attention to the organization of the text, as a result the Ss will fully understand the whole passage.3. ask Ss to retell the passage with the help of the key words in the form.Since the Ss in the class are in different levels, so I let them to fill in the blank to understand the meaning of the words and phrases better. ( That’s all for the while-reading. Now let’s move to the fifth step.)Step V: Post-reading (10mins) ---DiscussionIn this part students are asked to discuss in groups and list Wang Kun’s and Wang Wei’s attitudes about the trip. After that, Ss are encouraged to express their attitudes with the whole class. Collect their answers and don’t forget to praise them even if their answers may not be perfect.In this activity, discussion provides a vivid and active learning environment for Ss to communicate in English with newly learned language items. (Finally it comes to the homework.)StepⅥ: Homework (1min)1. Ss are required to read the text again after class and figure out the meaning of some complex sentences.2. Do the exercises on P19; This can help Ss to consolidate what they’ve learnt and make preparation for the next lessonPart4. Blackboard design.(说板书设计)On the top, there is the title of this lesson. On the left, there are main ideas for each paragraph. On the right, there are some new words and expressions.Unit 3 Travel journalJourney down the MekongMain idea of each para.:Para1: deciding to take a great bike trip along the Mekong river.Para2: Different attitudes between Wang kun and Wang wei.
Textbook: Senior English for China (Book 4), by Liu Daoyi Time Allotment: 1 period (40 minutes)Date: March 20, 2014Teaching aids: blackboard, Multi-media, Power Point, chalk I. Text Analysis (教材分析)This unit is about body language, and the text selected in the reading part demonstrates the difference and similarity of body language in many parts of the world. Through learning this passage, students are required to raise their awareness of using body language in different parts of the world. As body language is closely related to our daily life, it is easy to arouse students’ interest in learning this text. Reading skills and speaking training are designed around the text.II. Teaching Objectives (教学目标)By the end of the lesson, students will be able to:1. Language Skill Objective(语言技能目标): develop reading ability (skimming and scanning)as well as speaking ability.2. Cultural Knowledge Objective(文化知识目标): know about the cultural differences of using body language.3. Affective Objective(情感目标): increase students’ awareness of using body language correctly in different cultures. III.Teaching Focuses and Difficulties(教学重点和难点)1. Teaching Focuses(教学重点): the difference and similarity of body language in many parts of the world.2. Teaching Difficulties(教学难点): develop students’ reading abilities of skimming and scanning and ask the students to show their opinions with fluent English.
Step 7 Language points 1.Vocabulary (1) go through (2) set down (3) a series of (4) on purpose (5) in order to (6)at dusk (7)entirely (8)face to face 2.Important sentences (1)…I’ve grown so crazy about everything to do with nature. (2)There was a time when … (3)I stayed awake on purpose until … (4)It was the first time … that I’d seen the night … (5)It’s no pleasure looking through … Purpose: 1.Master the required vocabulary and sentence structures. 2.Use them freely. Step 8 Consolidation 1.Find out the topic sentences 2.Retell the text according to the topic sentences Purpose: I want to know if my students understand the text. Step 9 Discussion Imagine you have to go into hiding like Anne and her family, what would you miss most? Giveyour reasons. Purpose: Train Ss’ oral English ability. Step 10 Homework Write an article on Friends. Purpose: 1. Improve the Ss’ writing ability. 2 Train the Ss’ ability of self—teaching and looking up information by themselves. Part 5 Blackboard design(说板书设计)Unit 1 Friendship Reading Anne’s Best Friend 1.Main idea of each paragraph: Para. 1 Anne made her diary her best friend. Para .2 Anne wrote her feelings in her diary. Para .3 Anne missed nature. Para.4 Anne saw the night face to face Para.5 Anne wanted to experience nature outdoors. 2.Listening: Exx.1 P3 3.Discussion: Exx.3 P3 Purpose: 1.Make Ss familiar with the passage 2.Make the design inductive, instructive and artistic.
(3)v. 给:提出;展现,显现present sb. with sth. ; present sth. to sb. 把. . 交给;颁发;授予present sth. (for sth. )/present sth. to sb. e. g. Om his birthday, his friends presented him a collection of stamps. 在他生日时,他的朋友们送给他一套邮票作为礼物。The sword was presented by the family to the museum. 这家人把宝剑捐赠给了博物馆。The committee will present the final report to Parliament in June. 委员会将在六月向议会提交最后的报告。You need to present yourself better. 你需要更善于展现自己。It is essential that we present a united front. 至关重要的是我们要表现得更加团结。Step 4 ConsolidationT:Now that we have got a general idea of these words and phrases. Lets make up some sentences using them to master them. Suggested sentences:1. Your duties include typing letters and answering the telephone. 2. It is one of the greatest roles that she has played. 3. A large number of people have applied for the job. 4. The number of the panda is declining. 5. I'11 go there, even if I have to walk. 6. He came up to me to ask for a light. 7. The novel is about a family who can't communicate with each other. 8. He based his plan on interests of most people. 9. Why doesn't he make use of his singing talent?Step 5 Summary and homeworkT:Today we dealt with several new words and phrases. After class I hope that youcan read them again and again to keep them in mind. That's all for today. You aredismissed.
In this step, give students a few minutes to read the passage . While they are reading, I will write some key words of the text on the blackboard. Then ask students to retell the passage according to the key words.By retelling, students can improve their ability of language organization and have an overall understanding of the article.Step 4 Group discussionIn this step, students will be divided into groups of 4 to discussion the following question: What qualities make a great person?After their discussion, invite a few groups to make a report to the class.This group discussion can practice students’ oral English and cultivate their abilities of cooperation and communication.Step 5. HomeworkLet students write a short passage to introduce a great person he or she admires.The homework can consolidate the knowledge the students have learned and cultivate their writing ability. Part 6 Blackboard Design(板书设计)That’s all my teaching procedures. Finally, I’d like to say sth about part 6 blackboard design. On the top is the title. On the left, there will be some new words and expressions. In the middle of the blackboard, I will write some useful sentence structures so that the students can know clearly what they’ve learned and then try to master the knowledge.OK. That’s all for my presentation. Thank you for your attention.
一. 教材分析1. 本单元的中心话题是“计算机(Computers)”,内容涉及计算机的发展历史,计算机的应用等。本节课是该单元的第一课时,我将Warming up, Pre-reading and Comprehending这四部分整合为一节精读课。其中。Reading部分是题为WHO AM I?的文章,以第一人称的拟人手法介绍了计算机发长演变的历史和计算机在各个领域的应用,其主旨是表达计算机的发展变化之快以及在生活中用途之广。而Warming up部分以图片的形式展现了计算机的发展历程;Pre-reading中的问题和排序分别是为了预测语篇的内容和测试学生对计算机历史了解的情况;Comprehending则通过各项练习训练学生的阅读技能,从而加深对文章的理解。可见这几部分是一个有机的整体。2. 教学目标:1) 语言目标:重点词汇及短语:abacus, calculate, calculator, PC, laptop, PDA, robot, analytical, technological, universal, mathematical, artificial, intelligent, network, explore, in common, as a result.重点句子:a. My real father was Alan Turing, who in 1963 wrote a book to describe how computers could be made to work, and build a “universal machine” to solve any mathematical problem.
Ⅲ. Analysis of the teaching material:The topic of this unit is cultural relics. Students are quite interested in topics about different cultures around the world. This is the second period of the whole unit. As a reading class, the passage mainly talks about the history of the amber room (how it was made, sent as a gift, lost and rebuilt).According to the new national curriculum, when teaching reading, much emphasis should be put on training the students’ reading skills.Ⅳ. Teaching objectives1. Language objectives:1) Students are required to master the key words and phrases occurred in the passage (e.g. amazing, decorate, belong, in return, less than etc.)2) Students are required to learn the attributive clause and acquire the sentence pattern.2. 1) Students are required to describe a certain thing by using the new sentence patterns.2) Students are required to master two kinds of reading skills—skimming and scanning, and learn to use them in their daily reading.3. 1) Students are required to know the history of the amber room.2) Students are required to appreciate cultural relics and understand the importance of protecting them.Ⅴ. Teaching important and difficult points1) the new words, phrases, and sentence pattern in the course of reading.2) Teaching difficult point: Help the students master two kinds of reading skills—skimmingand scanning and learn to apply them in daily use.Ⅵ. Teaching methods:Task-based method & Top-down model Ⅶ. Teaching aids: PPT, pictures, blackboard Ⅷ. Teaching procedure:
Purpose of my design:To ask the students to do these two tasks will make the Ss predict the story of this passage. As a result, it will deepen Ss’ memory of this story because they will have their own understanding of this story.Step 3. While-readingTask 1. (Individual work _____min)Skimming: ask students to skim the text and the main ideas of each paragraph in this passage. Please read it quickly and then match the sentences with the letters.Task 2. (Individual work _____min)Scanning: read the text quickly and decide the whether the following statements are true or false and give reasons.Task 3. (Pair work _____min)Listen to the tape and fill in the banks. Then read the paragraph with expression to your partner.Task4 (individual work min)Listen to the tape again and write down the main idea in one sentence.Purpose of my design: Enable students to understand the given material better by using different reading skills. And proper competition can arouse the Ss’ interest in English learning. “Task-based” teaching method is used here todevelop the Ss’ ability of communication and also their ability of co-operation will be well trainedStep 4. Post-readingTask 1. (Individual work, pair work, group work, class work; _____min)Discussion (group of 4):1. If you were Hippomenes, would you run against Atlanta?2. Do you think Hippomenes deserved to win the race? Why or why not?Step 5. HomeworkPlease read the story again carefully after class and imagine: What will happen during the race between Hippomenes and Atlanta? Who do you think will win the race? Do you think Atlanta would marry Hippomenes? Write an end for the story with thses questions.Purpose of my design: Homework is so important and necessary for to master the knowledge they learned after class. It will check whether the Ss achieve the teaching aims.Part 5 Blackboard design
Step 2 Pre-listeningAfter students finish their discussion, I will show a picture of Newton and ask them: Who is him? What is he famous for? Could you find out some words to describe him? Maybe students will answer that he is genius for his finding of theGravitation, making a great contribution to the progress of human being. At that time I will show another two pictures of Einstein and Hawking, letting students guess who they are and write down their idea about the Gravitation. For I have arranged them to search more information about the gravity before this class, Students have beenfamiliar with the topic and will not be afraid about this abstract conception, which is helpful for their listening.Step 3 While-listeningIn this step, students will be required to listen the material for three times. The first and listening is extensive listening and the second and third listening is intensive listening. In the first time, They are required to listen a material including Part 1 and Part 2 and choose the best summary of the listening text. After they choose the right answer, They also need work in group to explain what is wrong with the others. Then I will make a conclusion that we should pay attention to the first paragraph and last paragraph and some keys to get the main idea. By doing this, their capacity of generalization will have a great improvement.Before the second listening, I will ask students to scan the blank on the power point quickly and ask them to note down some key words .Then ask them to listen to the Part 1again and fill the first column of the chart. Maybe some students just show the ideas of these three scientists an still can’t catch their development of gravity. Therefore, I will ask them to listen to Part 2 again and fill in the rest. After finish the listening, I will give them ten minutes to discuss with their partner. I will also guidethem to improve their answers when they discuss with others.
When it comes to the students’ studying methods, I'd like to introduce my Ss first. The Ss have a good command of basic language points. They’re interested in learning English, and they take an active part in English class, so they will have fun in autonomous, cooperative and inquiry learning. I will just serve as a guide, showing them the way to explore how to make more progress in their English learning.Now it’s time for the most important stage of this lesson. My teaching procedures are arranged as follows:Step1.Leading-in (3 minute)Play a video of a wide variety of wildlife to introduce my topic. Step2. Speaking (12 minutes)We will use our textbook Page25. Let the Ss fast read the short paragraph to warm up. Ask them to talk about the report on some endangered wildlife in China with the dialogue patterns on the screen. Lastly, I will invite some groups to demonstrate their dialogues about saving wildlife in China.Step3.English play (3 minutes)Watch another video in praise of their excellent performance just now. It’s about Jack Chen’s(成龙)and Yang Ziqiong’s wildlife protection.Step4. Listening (twice 13 minutes)This time, I’ll ask the Ss to fill in the blanks of the monologue of the 2 movie stars above. Step5.Discussion (3 minutes)Which would you like to choose to wear, clothes made of cotton, artificial leather or animal skins? Why ?Step6. Summary (3 minutes)1. If there were no wildlife, there wouldn’t exist human beings. If the buying stops, the killing can, too.2. Animals are our friends. To love animals is to love ourselves. Stop hunting, killing and destroying wildlife.3. Let’s live in harmony with all the living things in the world. Step7. Music appreciation (3 minutes)Let the Ss appreciate the song Earth Song by Michael Jackson. Last but not the least, I will show you my blackboard design.
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