Homework
Homework
I: Five words are italicized in the textbook passage below. Write the definition for each italicized word, choosing from the definitions in the box.
Be sure to read the entire passage before making your choices.
A:
In the early days of medicine, there were few drugs or treatments that gave any real physical benefit. As a result, patients were treated in a variety of strange, largely ineffective ways. For instance, Egyptian patients were medicated with “lizard ’s blood, crocodile dung, the teeth of a swine, the hoof of an ass, rotten meat, and fly specks.” If the disease itself didn ’t
cause the patient to succumb(I), he or she had a good chance of dying instead from the treatment. Medical treatments of the Middle Ages were somewhat less lethal(D), but not much more effective. And as late as the eighteenth century, patients were subjected to bloodletting, freezing, and repeatedly induced vomiting to bring about a cure.
Amazingly, people often seemed to get relief from such treatments. Physicians have, for centuries, been objects of great respect, and this was no less true when few remedies were actually effective. To what can one attribute the fair level of success that these treatments provided and the widespread faith in the effectiveness of physicians? The most likely answer is that these are examples of the tremendous power of the placebo effect – “any medical procedure that produces an effect in a patient because of its therapeutic intent and not its specific nature, whether chemical or physical.” Even today, the role of placebos in curtailing pain and discomfort is substantial. Many patients who swallow useless substances or who undergo useless procedures find that, as a result, their symptoms disappear and their health improves.
succumb:
lethal:
subjected to:
attribute:
curtailing:
B:
A century ago, the prevailing view among industrialists was that business had only one responsibility: to make a profit. By and large those were not good times to be a low-level worker or an incautious consumer. People worked sixty-hour weeks under harsh conditions for a dollar or two a day. The few people who tried to fight the system faced violence and unemployment. Consumers were not much better off. If you bought a product, you paid the price and took the consequences. There were no consumer groups or government agencies to come to your defense if the product was defective or caused harm. If you tried to sue the company, chances were you would lose.
These conditions caught the attention of a few crusading journalists and novelists known as muckrakers. They used the power of the pen to create public anger and agitate for reform. Largely through their efforts, a number of laws were passed to limit the power of monopolies and to establish safety standards for food and drugs.
Despite these reforms, business continued to pursue profits above all else until the Great Depression. When the economic system collapsed in 1929 and 25 percent of the work force was unemployed, people lost their faith in unbridled capitalism. Pressure mounted for government to fix the system.
At the urging of President Franklin Roosevelt, Congress voted in laws to protect workers, consumers, and investors. The Social Security system was set up, employees were given the right to join unions and bargain collectively, the minimum wage was established, and the length of the workweek was limited. Legislation was also enacted to prevent unfair competition and false advertising.
prevailing
agitate
unbridled
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enacted
II: The main idea may appear at any place within each of the three paragraphs that follow. Underline the main idea sentence for each paragraph.
1.With so many young, single people having babies, the question arises as to how
happy they are being young parents. A national survey of young, single mothers and fathers reveals that most were happier before they became parents.
Sixty-seven percent of the nine thousand new parents who responded to the survey said having a baby presented more problems than they envisioned. Fifty-six percent of the respondents said they had to drop out of school, despite their hopes that they could manage schoolwork plus rearing a baby. A majority (73%) said they were forced to seek financial help from family, friends and/or government agencies, and 37 percent said they accepted low-paying, unsatisfying jobs out of necessity. Also, 70 percent said they missed the “good times”with friends that they enjoyed before their babies were born.
2.To erase or not to erase? That is the question in many students’minds after
they’ve penciled in one of those small circles in multiple-choice tests. Folk wisdom has long held that when answering questions on such tests – or on any test –you should trust your first instincts. However, a research instructor has found that students who change answers they’re unsure of usually improve their scores.
The instructor spent three years compiling and analyzing college students’ tests, watching for telltale erasure marks, which would indicate that the student had, indeed, revised his or her answer. What the instructor found was that revised answers were two-and-a-half times as likely to go from wrong to right as vice-versa. This statistic held up even across such variables as sex, age, and race;
the subject matter of the tests studied also proved no to be a factor.
3.By the end of the first series of Sherlock Holmes stories, the author, Sir Arthur
Conan Doyle, had become tired of writing detective stories. So at the end of his second book of Holmes stories, he decided to have the detective die. The book ends with Holmes and his archenemy, Moriarty, plunging to their deaths from a high cliff overlooking a waterfall. After that, hundreds of letters poured in to Conan Doyle, begging him to bring Holmes back. Also, magazines offered him huge sums of money for additional Sherlock Holmes adventures. Finally, after nine years, Conan Doyle wrote a new story in which Holmes reappears and tells Dr. Watson that he did not die after all. Sometimes it is the reader, not the author, who determines how long fictional heroes will live.
初中英语情态动词详细用法归纳(含练习及答案)
初中英语情态动词详细用法归纳（含练习及答案） 1. can 的用法： （1）.表示能力、许可、可能性。表示能力时一般译为“能、会”，即有种能力，尤其是生来具备的能力.如：She can swim fast, but I can’t . 她能游得很快，但我不能。 I can see with my eyes. 我用眼睛看。could是can的过去式。表示过去的能力。 be able to do sth. 常常指经过努力，花费了时间和劳力之后才能做到某事。is/am/are able to do sth was/were able to do sth. （2）.表示许可，常在口语中。如：You can use my dictionary. 你可以用我的字典。 （3）.表示推测，可能性，意为“可能”，常用于否定句和疑问句中，此时can’t 译为“ 不可能”。如：Can the news be true? 这个消息会是真的吗？—Can it be our teacher?那个人有可能是我们老师吗？—No, it can’t be our teacher. He is on a visit to the Great Wall.不可能。咱们老师正在游览长城呢。 【例题】—I think Miss Gao must be in the library. She said she would go there. —No. She __be there, I have just been there. A.can’t B.mustn’t C.needn’t D.wouldn’t 【解析】根据下文“我刚去过那儿”可知，应为“ 不可能”，can’t 表示推测[答案] A could的用法： （1）.can的过去式，意为“ 能、会”，表示过去的能力。如：He could write poems when he was 10. 他十岁时就会写诗。 （2）. could在疑问句中，表示委婉的语气，此时could 没有过去式的意思。如:Could you give me a hand? 你能帮我个忙吗？—Could I use your pen? 我能用一下你的钢笔吗? —Yes, you can.可以。（用could问，不能用could答。） 2. may的用法： （1）.表示请求、许可，比can 正式，如：May I borrow your bike? 我可以借你的自行车吗？You may go home now. 现在你可以回家了。 【例题】—_______ I borrow your MP3? —Sure . Here you are. A. May B.Should C.Must D. Would 【解析】在此处表示请求，意为“ 做……可以吗”。答案：A (2) .表示推测，谈论可能性，意为“ 可能，或许”，一般用于肯定句中。如：It may rain tomorrow . 明天可能会下雨。She may be at home. 她可能在家呢. may not 翻译为“可能不” (3) .may的过去式为might ，表示推测时。可能性低于may。如：He is away from school. He might be sick. 他离开学校了，可能是他生病了。 (4) . 表示希望、祈求、祝愿，常可译为“祝愿”。通常是用may +主+V 例如：May you have a good time. 祝你过得愉快。May you be happy! 祝你幸福！May you succeed！祝你成功！ 3. must的用法： (1).must 表示主观看法，意为“必须、一定”。如：You must stay here until I come back.在我回来之前你必须呆在这儿。Must I finish my homework right now? 我必须现在交作业吗？(must引导的疑问句) 肯定回答：yes ,you must. 否定回答：No, you needn’t/ don’t have to (2) 其否定形式mustn’t表示“ 一定不要” “千万别” “禁止, 不许”. 如：You mustn’t play with fire. 你不许玩火。You mustn’t be late. 你一定不要迟到。 (3)must表示有把握的推测，用于肯定句,指百分百肯定。如: The light is on, so he must be at home now.灯亮着，他现在肯定在家。 （4）①must 和have to 都有”必须”的含义，但侧重点不同： must强调说话者主观(自己）的看法。 have to强调客观（外力作用）的需要，也可以翻译为“不得不”。
学术英语(管理类)单词
学术英语单词 第一单元 free enterprise自由企业制度 adversity不幸，逆境 capitalistic 资本主义的 compelling 令人信服的 array 大群，大量 stockholder 股东 work force 劳动力 prospective 可能的 underestimate 低估 dedication 奉献 perseverance 坚忍 mailable 可邮寄的 cooperative 合作完成的 on-demand 按要求的 billionaire 亿万富翁undercapitalization 资本不足convertible 敞篷汽车 sander 打磨机 vendor 卖家 stockbroker 股票经纪人 personality 名人 facet 一个方面 mutual fund 共同基金 oceanic evaporation 海洋蒸发 business plan 经营策划 customer service 顾客服务 fraud 欺骗 road map 指南 transaction 交易 price-targeting strategy 区别定价战略pricing 定价 hassle 困难，麻烦 self-targeting 使自己成为目标 prise 撬开 insensitive 不敏感的，反应迟钝的recipe 菜谱 make sth. of sb/sth. 利用（机遇）illuminating 使清楚易懂的 turn sth on its head使……与之前相反的premium 溢价 profitable 有利可图的 chili 小红辣椒 triple 使成三倍 markup 涨价 whopping 巨大的 crisp 薯片 snack 吃零食 admittedly 确实，无可否认的 irritated 生气的 outwit 以智取胜 close substitutes 功能接近的替代品 business landscape 商业格局，商业环境competitive dynamics 竞争的态势social web 社交网站 sicial networking site（SNS）社交网站Facebook Wall 脸谱的涂鸦墙 call center 呼叫中心 support staff 向客户提供支持的员工competitive advantage 竞争优势adoption of new technology 新技术的采用 log in 登陆 news feed 即使新闻，动态消息 target audience 目标受众 text message 手机短信 overestimate 高估 relevance 重要性 mainframe 主机 underway 在进行中 portal 门户网站 order of magnitude 数量级 traffic 受到访问 cohort 一批人 feat 事迹 technophobic 畏惧技术的 overly 太 unnavigable 无法导航的 anonymous 匿名的 blur 变模糊
homework1
《计算机系统基础》Homework HW1：数据的表示 实验目的：熟悉数值数据在计算机内部的表示方式，掌握相关的处理语句。 实验报告要求： 1.说明你做实验的过程（重要步骤用屏幕截图表示）。 2.提交源程序。 3.分析或回答问题。 完成下列实验，提交实验报告： 1.下述两个结构所占存储空间多大？结构中各分量所在位置相对于结构起始位置的偏移 量是什么？要求编写程序以验证你的答案。若使用#pragma pack(2)语句，则结果又如何？ struct test1 { char x2[3]; short x3[2]; int x1; long long x4; }; struct test2 { char x2[3]; short x3[2]; int x1; long long x4; }__attribute__((aligned(8))); 2.“-2 < 2”和“-2 < 2u”的结果一样吗？为什么？ 3.运行下图中的程序代码，并对程序输出结果进行分析。
4.运行下列代码，并对输出结果进行分析。 #include
学术英语管理课文翻译
Unit 1 When faced with both economic problems and increasing competition not only from firms in the united states but also from international firms located in other parts of the world, employee and managers now began to ask the question：what do we do now? although this is a fair question, it is difficult to answer. Certainly, for a college student taking business courses or be beginning employee just staring a career, the question is even more difficult to answer. And yet there are still opportunities out there d=for people who are willing to work hard, continue to learn, and possess the ability to adapt to change. 当面对不仅来自美国的公司而且来自位于世界其他地方的国际公司的经济问题和日益激烈的竞争时，员工和经理现在开始要问一个问题：我们要做什么？虽然这是一个很清晰的问题，但是它是很难回答的。当然，对于一个正在谈论商务课程的大学生或者一个刚开始职业生涯的员工来说，这个问题更难回答。但目前仍然有许多机会给那些愿意努力工作，继续学习并且拥有适应变化的能力的人。 Whether you want to obtain part-time employment to pay college and living expense, begin your career as a full –time employee, or start a business, you must bring something to the table that makes you different from the next person . Employee and our capitalistic economic systems are more demanding than ever before. Ask yourself: What can I do that will make employee want to pay me a salary? What skills do I have that employers need? With these questions in mind, we begin with another basic question: Why study business?
(完整word版)初一(1)homework趣味英语
让更多的孩子得到更好的教育 Homework A. Fill in the blanks with the correct form. Work, close, look, have, teacher, pen, eat, China, play, climb 1.This is our ___________ desk. Ours are over there. 2.Bill has three _____________. One is new and the other two are old. 3.His uncle _____________ very young but he is over forty. 4.Let's ______________ basketball after class. 5.Look! The cats are _______________ up the trees. 6.The shop isn't open. It's ______________. 7.My brother _______________ some new picture books. 8.In our classroom there is a large map of _______________. 9.Mum, please give me something to ______________. I'm very hungry. 10.Does Mr Green like _______________ in this Chinese school? B. Complete the following sentences. 11.I live with my family in a ________ (wood) house. 12.Look! The bus ________ (come). 13.Let's________(try) the Chinese restaurant in Star Shopping Mall. 14.John sometimes goes ________ (swim) in summer. 15.Three men in police uniform ran out of the ________ (build). You’ve got points in total 2013.07.05 让更多的孩子得到更好的教育
公共管理学作业homework答案
《公共管理学》homework（1） 一、名词解释 1.公共管理: 公共管理是指公公组织为解决公共问题，追求公共利益，运用公共权力，通过制定公共政策、有效地实行与监督等，提供公共物品和公共服务，维护公共秩序，对公共事务进行管理的社会活动。 2.公共选择理论公共选择理论是一门介于经济学和政治学之间的新兴交叉学科，它是运用经济学的分析方法来研究政治决策机制如何运作的理论。 3. 公共管理协调指协商、调整公共组织系统与其外部环境之间和系统内部的各种关系，使之权责清晰，分工合作，相互配合，有效地实现公共管理目标和提高整体效能的行为。 4. 公共管理监督是指依法对政府和公共事业组织等公共组织及其工作人员的监察和督导活动。 二、单项选择 1.1926年在美国出版两本权威的行政学教科书《行政学研究导论》《公共行政学原理》的两位学者分别是( B ) 25 A.泰勒和法约尔 B.怀特和威洛比 C.威尔逊和古德诺 D.马克斯?韦伯和赫伯特?西蒙 2.公共选择理论理论对政府的本质和行为的基本假设是( B)
A.社会人 B.经济人 C.自动人 D.复杂人 3.大萧条以后，为资本主义的稳定和发展起到了积极的作用的经济理论是( A ) A.凯恩斯的政府干预理论 B.新自由主义取消政府干预理论 C.亚当?斯密的“小政府”理论 D.古典经济学派的限制政府干预理论 4. 最早建立了比较规范的文官制度的国家是( A ) A.英国 B.法国 C.德国 D.美国 5. 18世纪英国著名经济学家________，在他著名的经济学著作《国富论》中对政府财政的管理范围和职能进行了限定。( C ) A.威廉?配第 B.马歇尔
初中英语情态动词讲解
情态动词 （一）情态动词的定义: 情态动词表示说话人对某一动作或状态的态度。 （二）情态动词的特点 1. 情态动词有一定的词义。 2. 情态动词不能单独做谓语，它必须和其他动词的原形一起构成谓语。 3. 情态动词没有人称，数的变化。 （三）情态动词的结构和意义 1.情态动词的基本句型 ?肯定句：主语+情态动词+动词原形+...... ?否定句：主语+情态动词+not+动词原形+...... ?疑问句：情态动词+主语+动词原形+...... 2. 情态动词的意义 must“必须”；can/could“能，会”；may/might “可以”；should“应该”； would“愿，要”；have to“不得不”；need“需要” （四）情态动词的基本用法 1.can (could主要指过去时间) 1）表示人或物本身所具有的能力，意为“能，能够，会” : Two eyes can see more than one. / I can swim very well. 2）表示可能（理论上或是逻辑判断上） He can’t (couldn’t) have enough money for a new car. 3）表示允许： Can I have a look at your new pen? He asked whether he could take the book out of the reading-room. 4）表示对现在动作或状态的猜测，主要用于否定句和疑问句中或感叹句中: He can’t (couldn’t) be over sixty.他不可能超过六十岁。 5）could表示比can更委婉客气的提出问题或陈述看法，指的是现在时间。 Can (Could) you lend me a hand? 帮我一把好吗？ 2. may (might) 1）表允许，询问或说明一件事可不可以做，might指过去时间；但在疑问句中might也可指现在时间，语气比may更委婉。 May (Might) I ask for a photo of your baby? 我可以要一张你宝宝的照片吗？ 在回答以may引起的问句时，肯定回答是一般可仍用may,或Yes, please. / Certainly./Sure./Of course. ； 否定回答根据说话人的语气由强到弱分别选用: must not(mustn’t)（禁止）/ had better not（最好别）/ may not（不行） 2) may表可能,但所表示的可能性不如can所表示的那样肯定。might可以指过去时间，也可以指现在时间，但语气更加不肯定。 He may be at home. 他可能在家。 They might be having a meeting, but I’m not sure.他们有可能在开会，不过我不肯定。 3. must（have to表示客观需要） 1）表示“必须”（主观看法）时，用于肯定句或疑问句；用于否定句时表示“禁止”。 We must do everything step by step. 我们一切都必须循序渐进地做。 You must get home before 9:00. 2）表示揣测。意为“想必、准是、一定”等，只用于肯定句。 He must be ill. He looks so pale. 他准是病了。他的脸色苍白。 3)must的疑问句，肯定回答用must，否定回答用needn’t或don’t have to。 4. should 1）表责任或义务，意为“应该”，用于各种人称。
homework_6
1. Linear prediction analysis is used to obtain an eleventh-order all-pole model for a segment of voiced speech that was sampled at a rate of Fs =8000 samples/second. The system function of the model is: 11 111 11()()11k k i k i G G G H z A z z z z α??=====??∑∏ Table 1 shows five of the roots of the eleventh-order prediction error filter,()A z . Table 1: Root locations of eleventh-order prediction error filter in the z-plane (a) Determine where the other six zeros of ()A z are located in the z-plane. If you cannot precisely determine the pole locations, explain where the pole might occur in the z-plane. (b) Estimate the first three formant frequencies(in Hz) for this segment of speech. (c) Which of the first three formant resonances has the smallest bandwidth? How is this determined? 2. A casual LTI system has system function: 1 12314()10.250.750.875z H z z z z ?????=??? (a) Use the Levinson-Durbin recursion to determine whether or not the system is stable. (b) Is the system minimum phase? 3. A speech signal frame (windowed using a Hamming window) has energy: (0)2 []1000n n m E s m ==∑ Using the autocorrelation method of analysis on this speech frame, the first 3
小学英语冀教版四年级上册《Lesson 7 Homework》同步练习
Lesson7 Homework 同步练习根据汉语意思写出单词 1. 晚上__________ 2. 作业__________ 3. 读__________ 4. 写__________ 5. 画__________ 6. 唱__________ 汉译英 1.你在晚上做什么？ _______________________________ 2.我做作业。 _______________________________ 给下列句子选择合适的汉语意思 ( ) 1. I read a book. ( ) 2. I write a story. ( ) 3. I do my homework. ( ) 4. I sing a song. A.我唱歌。 B.我读书。 C.我做作业。 D.我写故事。 单选题 1. What do you ________ in the evening? A. do B. does C. did D. dos 2. What do you do________ the evening? A. on B. at C. from D.in 英译汉 1. I draw a picture for my story.
_______________________________________ 2. This is the way I wash my clothes. _____________________________________________ 参考答案 根据汉语意思写出单词 1.Evening 2.Homework 3.Read 4.Write 5.Draw 6.sing 汉译英 Miss 1. What do you do in the evening? 解析：在晚上in the evening 2. I do my homework. 解析：do one’s homework做作业给下列句子选择合适的汉语意思 1.B 解析：固定搭配 2.D 解析：固定搭配 3.C 解析：固定搭配 4.A 解析：固定搭配 单选题 1.A 解析：What do you do... 询问做什么 2.英译汉D 解析：in the evening在晚上固定搭配 1.Betty 去参加聚会穿什么？为什么？ 1. 我为我的故事画一幅画。 2. 这是我洗衣服的方式。
初中英语情态动词讲解
初中英语情态动词用法详解 【情态动词知识梳理】 情态动词有具体的词义，但也同助动词一样，需要与其他词语一起构成句子的谓语，另外情态动词没有人称和数的变化，情态动词后必须跟动词原形。 1. can的用法： （1）.表示水平、许可、可能性。表示水平时一般译为“能、会”，即有种水平，尤其是生来具备的水平，此时may和must均不可代替它。如：She can swim fast, but I can’t . 她能游得很快，但我不能。I can see with my eyes.我用眼睛看。 （2）.表示许可，常在口语中。如：You can use my dictionary. 你能够用我的字典。（3）.表示推测，意为“可能”，常用于否定句和疑问句中，此时can’t译为“不可能”。如：Can the news be true?这个消息会是真的吗？—Can it be our teacher?那个人有可能是我们老师吗？—No, it can’t be our teacher. He is on a visit to the Great Wall.不可能。咱们老师正在游览长城呢。 【例题】—I think Miss Gao must be in the library. She said she would go there.—No. She __be there, I have just been there. 【解析】根据下文“我刚去过那儿”可知，应为“不可能”，can’t表示推测[答案] 2. could的用法： （1）.can的过去式，意为“能、会”，表示过去的水平。如：He could write poems when he was 10. 他十岁时就会写诗。 （2）. could在疑问句中，表示委婉的语气，此时could没有过去式的意思。如：Could you do me 你能帮我个忙吗？—Could I use your pen?我能用一下你的钢笔吗?—Yes, you can.能够。（注意回答） 3. may的用法： （1）.表示请求、许可，比can正式，如：May I borrow your bike?我能够借你的自行车吗？You may go home now.现在你能够回家了。 【例题】—_______ I borrow your MP3?—Sure . Here you are. A. May B.Should C.Must D. Would
高中英语优质课课件Homework
Homework Revision for Book 6 Unit 2 Poems 惠州市光正实验学校曹慧嫱 Ⅰ. Go over the words and the phrases of Unit 2. Prepare for the dictation of this unit. Ⅱ. Go over the content of the Subjunctive Mood on Page 86-87 in your textbook. Ⅲ. Finish the exercises below: 一. 用本单元所学单词的适当形式填空 1. The message __________ (传达)here is clear: Actions speak louder than words. 2. They are trying hard to reduce the harm caused by pollution to a ____________ (最低限度). 3. The company where her father works is one of the _________ (赞助商) of the Olympic Games. 4. Is it an a_______________ time to make a speech now? 5. I’m fully aware that it’s the experience from my life abroad has totally t___________ me. 6. To his s__________, he lost all his possessions because of his failure in his business. 7. Are you doing anything _____________ (particularly) tonight? 8. As a matter of fact, employees expect to work ____________ (flexible) in the workplace. 9. Any behavior that is repeated enough times will ___________ (eventual) become a habit and happen automatically. 10. He is good at English _____________ and has ___________ many novels. (translate) 二、单句写作 1. In this letter, I would like to _________________________ for your assistance. 对于您的帮助，我想在这封信中表达对你的感谢。 2. ______________, and you will be all right in a couple of days. 别担心，过几天你就会痊愈的。 3. About 5% of the US population _____________________ American Indians. 美国人口的大约百分之五是由美国印第安人组成。 4. Mothers holding jobs outside the home __________________ to make it easier to care for their children. 在家庭外有工作的妈妈应该有灵活的工作时间表，这样他们就能照看孩子更容易些。 5. We are __________________________ the petrol. We must find a gas station immediately. 我们的汽油快用完了，我们必须赶快找到加油站。 6. Sports clothes _______________________ a formal wedding. 运动服不适合在正式婚礼中穿。 7. We students ____________________________________________, who are rich in experience, and above all, love us most in the world. 我们学生应该经常和父母交换想法，他们经验丰富，而且最重要的是，在这个世界上他们是最爱我们的人。 8. I can tell you the truth, but you must promise ________________________. 我可以告诉你真相，但你要承诺不要泄露秘密。 9. The inventor is excited, and he is going to ___________________________. 这位发明家很兴奋，他要试一下他的新机器。 10. If_____________________________ (没有电)，what would happen? 11. How I wish you _______________________________ (能来参加聚会) this weekend. 12. 要不是你对伤员进行急救的话，他早就死了。 _______________________________________________________________________________ 13. 你如果对计划早点儿做出调整，就不会陷入困境了。 _______________________________________________________________________________ 14. Grace doesn’t want to move to New York because she thinks if she ___________ (居住) there, she wouldn’t be able to see her parents very often. Homework Revision for Book 6 Unit 2 共1页
homework 5
Homework5 Due to3:30pm,5Nov致知楼2楼教员休息室 1.Let x and y are positive numbers.Please design a Turing Machine (diagram)to compute x×y(multiple of x and y).You should explain the notation of x and y.Hint:you may get the notation as simple as you can. 2.If L is a language,and a is a symbol,then L/a,the quotient of L and a,is the set of strings w such that wa is in L.For example, if L={a,aab,baa},then L/a={ε,ba}.Prove that if L is regular,so is L/a.Hint:Start with a DFA for L and consider the set of accepting states. 3.Show that the regular languages are closed under the following operations:min(L)={w|w is in L,but no proper prefix of w is in L}. https://www.wendangku.net/doc/6115541672.html,e the CFL pumping lemma to show that the following language is not context free {a i b j c k|i 第6周homework 1答案 Have you ever felt lumps under the skin on the sides of your neck when you were sick? Those might be lymph nodes. 1.They can get swollen and painful but their job is to fight infection. Lymph nodes are part of the body's defenses known as the lymphatic system. 2.This complex system throughout the body makes and transports a protective fluid called lymph. 3.Lymph is made of white blood cells, proteins and fats. In a patient with breast cancer, the cancer can spread to the large number of lymph nodes under the arm. 4. Doctors have traditionally removed many of these lymph nodes in the hope of removing all the cancer. But the latest research finds nothing to gain by removing so many lymph nodes. Doctors have two choices when breast cancer starts to spread. They can do what is called a sentinel node biopsy. They remove the main growth and one or 2 lymph nodes nearest to it. 5.Or they can take more aggressive action and remove a lot of lymph notes. 6. But that can lead to shoulder pain and permanent swelling o f the arm. 第6周homework 2答案 Now the Earth Policy Institute in Washington has issued a bleak warning of the risk of environmental and economic 1. chaos. Its founder Lester Brown says a push towards sustainability could help. In fact, he says, it's essential. In this week's Global Business, Peter Day hears why. Lester Brown started life as a farmer in New Jersey, the Garden State in the USA. He got some hefty degrees, worked at home and abroad for the US Department of Agriculture, and then in 1974, he founded the World Watch Institute. It became well-known for its 2. annual state of the world reports on the global environment. Years ago when I had one of our 3. periodic chats at the World Watch Institute in Washington D.C., I remember a room decked with satellite maps of the world's watershed areas. Water is still an 4.abiding theme for Lester Brown in his newer role as founder and head of the Earth Policy Institute. It's another Washington D.C. think tank designed to provide a road map for building a 5.sustainable economy. But even after so many years on the environmental beach, there's a new urgency in what Lester Brown is saying in the book World on the Edge. As an agriculturist by training, he 6.focuses on food and the new threat of food scarcity caused by natural disasters,such as the Russian drought last summer, and 7.consequential flooding elsewhere, and increasing demand for many developing countries as well as the rich world. Lester Brown thinks 8.the world has to mobilize to embrace sustainability in the way第6周homework 答案