1. 設(shè)全集U={1.2.3.4.5}.集合A={1.2}.B={2.3}.則A.{4.5} B.{2.3} C.{1} D.{2} 查看更多

 

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Caring for animals, tutoring kids, helping seniors: Volunteer hours are more than a graduation must, they are life lessons.

    Vilma Sooknanan cleans cat cages, Max Carroll teaches children how to cook and Michael Rosenthal rolls wheelchairs at a hospital.

    What does this have to do with high school education?

    Everything.

    The three – and almost all other South Florida high school students – have to go outside of the classroom to earn their diplomas, doing what schools call “community service”.

    Broward public schools require 40 hours to graduate. Palm Beach County public schools require 20, and most private schools require at least that much.

    The purpose: To give students the chance to explore a career and create a habit of volunteering.

    “We hope that when they finish high school they’ll continue service,” says Mike Roland, student activities officer for the Broward School District.

    About half of U.S. public schools require community service, according to a national study. Broward School Board member Bob Parks says encouraging community service has launched all kinds of new projects, including tutoring and food collections.

    Sooknanan, a student at South Broward High School, is part of the Humane Society of Broward County’s volunteer program, which is so popular that even the waiting list is closed. Students work one four-hour shift a week for four months, and leave with 64 volunteer hours.

    Sooknanan changes litter boxes and puts down fresh newspaper for about 100 cats.

    Combined with her volunteer hours at beach cleanups and helping teachers at school, she’s well on her way toward 250 hours, which she hopes will catch the eye of Nova Southeastern University, where she wants to study marine biology.

    Carroll, a junior student at South Plantation High, has connected with FLIPANY, a nonprofit organization that offers cheap physical activity and food to low-income families. He helps teach children about cooking and healthy eating.

    “It has been a life-changing experience,” says Carroll, who is now leaning toward a career as a sports trainer. "I want to find a career encouraging people to lead a healthier lifestyle.”

(Note: Answer the questions or complete the statements in NO MORE THAN 15 WORDS.)

 

1. How many hours of community service are students required to do to graduate from most U.S. private schools?

 

2. Why do some U.S. schools require students to do community service to graduate?

 

3. The reason Sooknanan take up so many kinds of volunteer work is that ___________.

 

4. Volunteer work is popular in many high schools in the U.S., not only because it is a graduation must, but also because ___________ .

 

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Chinese President Hu Jintao, on his way to talks with President George W. Bush in Washington, on Tuesday met with Bill Gates. 

After the meeting with Gates, the world's richest man, at Microsoft's headquarters, Hu restated that China would move against software pirates all the time(盜版軟件).

At Microsoft Corp.'s campus, Hu said Tuesday he admired what Microsoft Chairman Bill Gates had achieved. He also sought to reassure Gates that China is serious about protecting intellectual property rights(知識(shí)產(chǎn)權(quán)).

"Because you, Mr. Bill Gates, are a friend of China, I'm a friend of Microsoft," Hu said.

"Also, I am dealing with the operating system produced by Microsoft every day," he added, to laughter.

Gates responded: "Thank you, it's a fantastic relationship," and then said: "And if you ever need advice on how to use Windows, I'll be glad to help."

"China is focused on and has already accomplished much in creating and enforcing laws to protect intellectual property." he said. "We take our promises very seriously."

Hu also said he would certainly welcome a further increase in Microsoft's investment in China.

"I'd also like to take this opportunity to assure you, Bill Gates, that we will certainly honor our words in protecting intellectual property rights," Hu said.

In his brief visit to the Microsoft campus, Hu, accompanied by Gates and company CEO Steve Ballmer, saw some business technology demonstrations and toured Microsoft's Home of the Future, which features experimental technology that might someday be used in people's living spaces.

Following the visit at Microsoft, about 100 guests, including former Secretary of State Henry Kissinger and former Gov. Gary Locke, the first Chinese-American governor, were invited to Gates' $100 million lakeside house on Lake Washington for a dinner.

China has recently begun requiring Chinese computer makers to load legal software on their machines.

In Seattle's Chinatown, many stores hung Chinese and U.S. flags to welcome Hu, and many in the crowd outside the stately Fairmont Hotel on Monday night where Hu is staying were there to support the Chinese president.

How many issues are mentioned in President Hu’s visit to Microsoft?

A. one    B. two   C. three   D. four

Put the sentences in correct order.

Hu had a meeting with President George W. Bush

Hu had dinner with many guests in Gates’ lakeside house

Hu paid a visit to the Microsoft campus

Hu stayed at Fairmont Hotel in Seattle

A. 4-3-2-1     B. 4-2-3-1      C. 1-4-3-2     D. 1-3-2-4

What measure is not mentioned to protect intellectual property rights?

A. Moving against software pirates

B. creating and enforcing laws

C. increasing Microsoft's investment in China

D. requiring Chinese computer makers to load legal software on their machines

What is the best title for the passage?

A. Hu Visits Microsoft                  B. Protecting Intellectual Property Rights

C. Bill Gate’s, A Friend of China          D. Americans Welcome President Hu

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When Scotsman Alexander Graham Bell invented the telephone in 1876, it was a revolution in communication. For the first time, people could talk to each other over great distances almost as clearly as if they were in the same room. Nowadays, though, we increasingly use Bell’s invention for taking photographs, accessing the internet, or watching video clips, rather than talking. Over the last two decades a new means of spoken communication has appeared: the mobile phone.

         The first real mobile telephone call was made in 1973 by Dr Martin Cooper, the scientist who invented the modem mobile handset(手機(jī)). Within a decade, mobile phones became available to the public. The streets of modem cities began to feature sharp-suited characters shouting into giant plastic bricks. In Britain the mobile phone quickly became the same with the “yuppie”, the new type of young urban professionals who carried the expensive handsets as status symbols. Around this time many of us said that we would never own a mobile phone.

         But in the mid-90s, something happened. Cheaper handsets and cheaper calling rates meant that, almost overnight, it seemed that everyone had a mobile phone. And the giant plastic bricks of the 80s had changed into smooth little objects that fitted nicely into pockets and bags.

         Moreover, people’s timekeeping changed. Younger readers will be amazed to know that, not long ago, people made spoken arrangements to meet at a certain place at a certain time. But later Meeting time became approximate under the new order of communication: the Short Message Service (SMS) or text message. Going to be late? Send a text message! It takes much less effort than arriving on time, and it’s much less awkward than explaining your lateness face to face and the text message has changed the way we write in English. Traditional rules of grammar and spelling are much less important when you’re sitting on the bus, hurriedly typing “Will B 15mm late - C U @ the bar. Sorry! -).”

         Alexander Graham Bell would be amazed if he could see how far the science of telephony has progressed in less than 150 years. If he were around today, he might say “That’s gr8! But I’m v busy rite now. Will call U 2nite.”

1.What does the underlined part in Para.2 refer to?

A. Houses of modern cities.                      B. Sharp-suited characters.

C. New type of professionals.                    D. Mobile phones.

2.According to Paragraph 4, why did Meeting time become approximate?

A. People were more likely to be late for their meeting.

B. SMS made it easier to inform each other.

C. Young people don’t like unchanging things.

D. Traditional customs were dying out.

3.If you want to meet your friend at the school gate this evening, which of the following message can you send him?

A. Call U@ SKUg8 2nite.                   B. IM2BZ2CU 2nite.

C. CU@ the bar g8 2nite.                   D. W84U@ SKUg8 2nite.

4.What does the passage mainly tell us about?

A. Alexander Graham’s invention.

B. SMS as a new way of communication.

C. New functions of the mobile telephone.

D. The development of the mobile phone.

 

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Can you understand the beginning of this essay?

“My smmr hols wr CWOTT. B4, we usd 2go2 NY 2C my bro, his GF & 3 kds FTF.”

The Scottish teacher who received it in class had no idea what the girl who wrote it meant. The essay was written in a form of English used in cell phone text messages. Text messages (also called SMS2) through cell phones became very popular in the late 1990s. At first, mobile phone companies thought that text messaging would be a good way to send messages to customers, but customers quickly began to use the text messaging service to send messages to each other. Teenagers in particular enjoyed using text messaging, and they began to create a new language for messages called texting.

A text message is limited to 160 characters, including letters, spaces, and numbers, so messages must be kept short. In addition, typing on the small keypad of a cell phone is difficult, so it’s common to make words shorter. In texting, a single letter or number can represent a word, like “r” for “are,” “u” for “you,” and “2” for “to.” Several letters can also represent a phrase, like “l(fā)ol” for “l(fā)aughing out loud.” Another characteristic of texting is the leaving out of letters in a word, like spelling “please” as “pls.”

Some parents and teachers worry that texting will make children bad spellers and bad writers. The student who wrote the essay at the top of this page said writing that way was more comfortable for her. (The essay said, “My summer holidays were a complete waste of time. Before, we used to go to New York to see my brother, his girlfriend, and their three kids face to face.”)

Not everyone agrees that texting is a bad thing. Some experts say languages always evolve, and this is just another way for English to change. Other people believe texting will disappear soon. New technology for voice messages may soon make text messages a thing of the past.

1.What is the writer’s opinion of text messaging?

A. It is fun and easy to do.

B. It is not bad for children.

C. It will make children bad writers.

D. The writer does not give an opinion.

2.Which characteristic of texting is NOT described in the passage?

A. Using phrases to represent essays

B. Using numbers to represent words

C. Using letters to represent phrases

D. Using letters to represent words

3.Which of the following was most probably the title of the student’s essay?

A. My Gr8 Tchr          B. CU in LA          C. My GF        D. My Smmr Hols

4.  Why do some people think that texting is bad?

    A. It costs too much.                           B. It’s too difficult to type.

    C. Children won’t learn to write correctly.          D. It’s not comfortable.

5.Why aren’t some people worried about the effect of texting?

A. Not many people use texting.

B. Spelling in English is too difficult.

C. Children quickly become bored with texting.

D. Texting will disappear because of new technology.

 

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Is there a nationwide shortage of nurses? It’s hard to say.However, some characteristic symptoms often indicate that there is indeed a shortage.
One symptom is the vacancy rate, or the percentage of budgeted positions that are unfilled.New England’s hospitals currently report that an average of 7 to 12 percent of their registered nurse positions are vacant, the highest level since the last shortage in the late 1980s.Vermont has a relatively low vacancy rate, at 7.8 percent.But its vacancies were at 1.2 percent just five years ago.
Another symptom is the increased use of stopgap measures to fill empty positions.For instance, many nurses report an upswing in how frequently they are asked to stay past their shifts.According to Murphy, working in the St.Elizabeth’s Hospital, “The shortage has definitely created a lot of opportunities of overtime for our nurses, whether they want them or not.” Similarly, a national survey of registered nurses shows that in an average week, nurses in the U.S.work 2.4 more hours than they are scheduled to.Much of this extra time is voluntary, as nurses earn overtime pay when they stay to fill in blanks in the schedule.
When they can’t fill open positions by more traditional means, health care providers hire temporary staff to tide them over.Travelling workers are the largest part of the temporary health care workforce, hired for thirteen-week reduction at health care facilities facing short-term lack of workers.Temporary workers, mainly nurses, cost hospitals $ 7.2 billion in 2000.
“Any successful solution to the shortage depends on convincing more people to become nurses, and that is not an easy goal to reach.To achieve it,” says Buerhaus, “society needs to place more value on nursing.Legislation (法規(guī)) can’t do that – it should come from people.” And if this continues, we might have to learn to care for ourselves in the hospital.
【小題1】The temporary staff hired by a hospital _______.

A.cost a large part of the hospital’s budget
B.meet the need for nurses in the hospital for a short time
C.should work on a weekly basis and on a scheduled timetable[來(lái)源:學(xué)科網(wǎng)ZXXK]
D.ought to work passively for thirty continuous weeks
【小題2】According to Buerhaus, what is a successful solution to the nurse shortage?
A.To convince people of the benefits of being a nurse.
B.To ask the government for help to work out specific legislation.
C.To publicize the past achievements of nurses.
D.To make people aware of the importance of being a nurse.
【小題3】What’s the probable meaning of the underlined word “upswing” in Paragraph 3?
A.SymptomB.DecreaseC.IncreaseD.Figure
【小題4】What’s the author’s attitude towards nurse shortage?
A.WorriedB.IndifferentC.DoubtfulD.Optimistic

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1.C   2.A   3.B   4.D   5.C   6.B   7.D   8.C   9.B  10.A

  11.120°   12.3x+y-1=0   13.   14.10    15.100    16.(1),(4)

17.解:(1)設(shè)拋物線(xiàn),將(2,2)代入,得p=1. …………4分

∴y2=2x為所求的拋物線(xiàn)的方程.………………………………………………………5分

(2)聯(lián)立 消去y,得到. ………………………………7分

設(shè)AB的中點(diǎn)為,則

∴ 點(diǎn)到準(zhǔn)線(xiàn)l的距離.…………………………………9分

,…………………………11分

,故以AB為直徑的圓與準(zhǔn)線(xiàn)l相切.…………………… 12分

(注:本題第(2)也可用拋物線(xiàn)的定義法證明)

18.解:(1)在△ACF中,,即.………………………………5分

.又,∴.…………………… 7分

(2)

. ……………………………14分

(注:用坐標(biāo)法證明,同樣給分)

19.

解法一:(1)連OM,作OH⊥SM于H.

∵SM為斜高,∴M為BC的中點(diǎn),∴BC⊥OM.

∵BC⊥SM,∴BC⊥平面SMO.

又OH⊥SM,∴OH⊥平面SBC.……… 2分

由題意,得

設(shè)SM=x,

,解之,即.………………… 5分

(2)設(shè)面EBC∩SD=F,取AD中點(diǎn)N,連SN,設(shè)SN∩EF=Q.

∵AD∥BC,∴AD∥面BEFC.而面SAD∩面BEFC=EF,∴AD∥EF.

又AD⊥SN,AD⊥NM,AD⊥面SMN.

從而EF⊥面SMN,∴EF⊥QS,且EF⊥QM.

∴∠SQM為所求二面角的平面角,記為α.……… 7分

由平幾知識(shí),得

,∴

,即所求二面角為. ……………… 10分

(3)存在一點(diǎn)P,使得OP⊥平面EBC.取SD的中點(diǎn)F,連FC,可得梯形EFCB,

取AD的中點(diǎn)G,連SG,GM,得等腰三角形SGM,O為GM的中點(diǎn),

設(shè)SG∩EF=H,則H是EF的中點(diǎn).

連HM,則HM為平面EFCB與平面SGM的交線(xiàn).

又∵BC⊥SO,BC⊥GM,∴平面EFCB⊥平面SGM. …………… 12分

在平面SGM中,過(guò)O作OQ⊥HM,由兩平面垂直的性質(zhì),可知OQ⊥平面EFCB.

而OQ平面SOM,在平面SOM中,延長(zhǎng)OQ必與SM相交于一點(diǎn),

故存在一點(diǎn)P,使得OP⊥平面EBC. ……………………… 14分

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      ∵底面邊長(zhǎng)為1,∴,

      ,

      .    ……………… 1分

      設(shè)

      平面SBC的一個(gè)法向量,

      ,

      ∴y=2h,n=(0,2h,1).… 3分

      =(0,1,0),由題意,得.解得

      ∴斜高. …………………………………………………… 5分

      (2)n=(0,2h,1)=,

      由對(duì)稱(chēng)性,面SAD的一個(gè)法向量為n1. ………………………………6分

      設(shè)平面EBC的一個(gè)法向量n2=(x,y,1),由

      ,,得

       解得.………………… 8分

      設(shè)所求的銳二面角為α,則

      ,∴.…………… 10分

      (3)存在滿(mǎn)足題意的點(diǎn).證明如下:

      . ………………………… 11分

      ,令與n2共線(xiàn),則. ……………… 13分

      .故存在P∈SM,使OP⊥面EBC.……………………… 14分

      20. 解:(1)當(dāng)n為奇數(shù)時(shí),an≥a,于是,. ………………3分

               當(dāng)n為偶數(shù)時(shí),a-1≥1,且an≥a2,于是

      =. …………6分

      (2)∵,,,∴公比.……9分

      . …………………………………………10分

      (注:如用求和公式,漏掉q=1的討論,扣1分)

       . ……………12分

      .……15分21.解:(1)∵,,∴,∴. 1分

      ,即,∴. …3分

      ①當(dāng),即時(shí),上式不成立.………………………………………………4分

      ②當(dāng),即時(shí),.由條件,得到

      ,解得. ……………………………………………5分

      ,解得.…………………………………………6分

       m的取值范圍是. ………………………………………7分

      (2)有一個(gè)實(shí)根.………………………………………………………………………………9分

      ,即

      ,則

      ,. ………………………10分

       △>0,故有相異兩實(shí)根

      ,∴ 顯然,

      ,∴,∴. …………12分

      于是

                          

      為三次函數(shù)的極小值點(diǎn),故與x軸只有一個(gè)交點(diǎn).

      ∴  方程只有一個(gè)實(shí)根.…………………………15分


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