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计算:(4b-3ab)+(-5b+3ab)

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朱禧看到山石中有贝壳,认为“此石即旧日之土,螺蚌即水中之物,下者却变而为高,柔者却变而为刚。”这体现了
A.三纲五常B.发明本心C.格物致知D.经世致用

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(8分)供电局某工程队在冬天架设电线,如图所示,设两电线杆间距离为L,铜导线总质量为M,电线架好后,在两杆正中部位电线下坠的距离为h,电线在杆上固定处的切线方向与竖直方向的夹角为θ,求:

(1)两电线杆处的电线弹力.
(2)当到夏天时,两电线杆处的电线弹力与冬天相比是变大了,还是变小了?为什么?(提示:导线上每处的弹力均沿切线方向)

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科目: 来源: 题型:阅读理解

Jiuzhaigou is a very beautiful place. It is in the Aba Tibetan and Qiang Autonomous Region in Sichuan Province. Jiuzhaigou is a valley. It is more than 40 kilometers long. The green and golden trees, the lofty and multi-shaped mountains and the clear and colorful waters form the unique beauty of Jiuzhaogou. The water of Jiuzhaigou is the soul of the beauty. There are more than 100 lakes of different shapes in the valley. These lakes have wonderful colors. They are called “haizi”, which means son of the sea. It is these beautiful lakes that make Jiuzhaigou a fantastic place. Between the forests and the lakes, there are nine Tibetan villages. The name Jiuzhaigou means Nine Village Valley.
Jiuzhaigou was discovered because of a panda rescue program. The pandas were once endangered because the bamboo there was blooming. When people came to rescue the pandas, they were surprised by the beauty of Jiuzhaigou. After that, Jiuzhaigou became a protected scenic area.
In China, there is a saying which goes like this: No mountain is worth seeing after you have seen Mount Huang and no other body of water will attract you after you have visited Jiuzhaigou. The beauty of Jiuzhaigou cannot be described with mere words. The best way to enjoy this fairyland is to go there. See you in Jiuzhaigou.
【小题1】 What is the best title for the passage? (no more than 3 words)
_____________________________________________________________
【小题2】 How long is the Jiuzhaigou Valley? (no more than 7 words)
_____________________________________________________________
【小题3】 How was the Jiuzhaigou Valley discovered? (no more than 9 words)
【小题4】 What does the name Jiuzhaigou mean? (no more than 7 words)
_____________________________________________________________

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科目: 来源: 题型:阅读理解

Jiuzhaigou is a very beautiful place. It is in the Aba Tibetan and Qiang Autonomous Region in Sichuan Province. Jiuzhaigou is a valley. It is more than 40 kilometers long. The green and golden trees, the lofty and multi-shaped mountains and the clear and colorful waters form the unique beauty of Jiuzhaogou. The water of Jiuzhaigou is the soul of the beauty. There are more than 100 lakes of different shapes in the valley. These lakes have wonderful colors. They are called “haizi”, which means son of the sea. It is these beautiful lakes that make Jiuzhaigou a fantastic place. Between the forests and the lakes, there are nine Tibetan villages. The name Jiuzhaigou means Nine Village Valley.
Jiuzhaigou was discovered because of a panda rescue program. The pandas were once endangered because the bamboo there was blooming. When people came to rescue the pandas, they were surprised by the beauty of Jiuzhaigou. After that, Jiuzhaigou became a protected scenic area.
In China, there is a saying which goes like this: No mountain is worth seeing after you have seen Mount Huang and no other body of water will attract you after you have visited Jiuzhaigou. The beauty of Jiuzhaigou cannot be described with mere words. The best way to enjoy this fairyland is to go there. See you in Jiuzhaigou.
【小题1】 What is the best title for the passage? (no more than 3 words)
_____________________________________________________________
【小题2】 How long is the Jiuzhaigou Valley? (no more than 7 words)
_____________________________________________________________
【小题3】 How was the Jiuzhaigou Valley discovered? (no more than 9 words)
【小题4】 What does the name Jiuzhaigou mean? (no more than 7 words)
_____________________________________________________________

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(8分)电浮选凝聚法是工业上采用的一种处理污水方法,下图是电解污水实验装置示意图。接通直流电源后一段时间,在A电极附近有深色沉淀物沉积下来,在B电极附近有气泡产生。气泡可将污水中的悬浮物带到水面形成浮渣层,积累到一定厚度时刮去浮渣层,即起到了浮选净化的作用。

试根据以上实验现象以及图示回答下列问题:
(1)电解池的电极A、B极性分别为              (填 “阴极”、“阳极” )
(2)实验时若污水中离子浓度较小,导电能力较差,产生气泡速率缓慢,无法使悬浮物形成浮渣。此时,应向污水中加入适量的           
a.H2SO4     b.BaSO4     c.Na2SO4     d.NaOH     e.CH3CH2OH
(3)电解池阳极的电极反应分别是①              ;②4OH- 4 e= 2H2O +O2↑。
(4)电极反应①和②的生成物反应得到Fe(OH)3沉淀的离子方程式是                   

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(8分)电浮选凝聚法是工业上采用的一种处理污水方法,下图是电解污水实验装置示意图。接通直流电源后一段时间,在A电极附近有深色沉淀物沉积下来,在B电极附近有气泡产生。气泡可将污水中的悬浮物带到水面形成浮渣层,积累到一定厚度时刮去浮渣层,即起到了浮选净化的作用。

试根据以上实验现象以及图示回答下列问题:
(1)电解池的电极A、B极性分别为              (填 “阴极”、“阳极” )
(2)实验时若污水中离子浓度较小,导电能力较差,产生气泡速率缓慢,无法使悬浮物形成浮渣。此时,应向污水中加入适量的           
a.H2SO4     b.BaSO4     c.Na2SO4     d.NaOH     e.CH3CH2OH
(3)电解池阳极的电极反应分别是①              ;②4OH- 4 e= 2H2O +O2↑。
(4)电极反应①和②的生成物反应得到Fe(OH)3沉淀的离子方程式是                   

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科目: 来源: 题型:阅读理解


America is a mobile society. Friendships between Americans can be close and real, yet disappear soon. They don ’t feel hurt. If the same two people meet again, even years later, they pick up the friendship .This can be quite difficult for us Chinese to understand .Friendships between us develop more slowly but may become lifelong feelings, extending(延伸)deeply into both families.
There is another difficult point for us to understand . Although Americans treat friends warmly in their personal everyday lives, they don’t show their politeness to them if it requires a great deal of time. But in China ,we are usually generous with our time. We, as hosts, will appear at an airport even in the middle of the night to meet a friend. We may take days off from our work to act as guides to our friends .It is opposite in America , Americans can not manage the time to do a great deal with a visitor outside their daily plans. They will probably expect the visitors to get themselves from the airport to the hotels. And they expect the visitors will phone them from there. Once the visitors arrive at their homes , the welcome will be full , warm and real. For Americans , it is often considered more friendly to invite a friend to their homes than to restaurants, except for business matters. Americans are ready to receive us foreigners at their homes, share their holidays, and their home life. So accept their hospitality(好客)at home and enjoy your visit in America!
【小题1】The underlined phrase “pick up” in Paragraph 1 may mean “_______”.
A.keep outB.give upC.pay no attention toD.continue
【小题2】Which of the following is the typical (典型的)way of  American hospitality?
A.Treating friends at home.
B.Taking days off to be with friends.
C.Meeting friends at the airport at midnight.
D.Sharing everything they have.
【小题3】Which of the following statements is True according to the passage?
A.Americans are always generous with their time.
B.Americans don’t feel hurt if their friendships disappear soon.
C.Chinese friendships develop more slowly but will never disappear.
D.Chinese friendships are more sincere than American friendships.

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德国法学家耶林认为:“罗马曾三次征服了世界,第一次是武力,第二次是宗教,第三次则是以法律。”古代罗马之所以能以法律征服世界,是因为罗马法中流传后世的原则是
A.法律面前人人平等,公正至上B.以眼还眼,以牙还牙
C.礼不下庶人,刑不上大夫D.妇女不得参加任何事务

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德国法学家耶林认为:“罗马曾三次征服了世界,第一次是武力,第二次是宗教,第三次则是以法律。”古代罗马之所以能以法律征服世界,是因为罗马法中流传后世的原则是
A.法律面前人人平等,公正至上B.以眼还眼,以牙还牙
C.礼不下庶人,刑不上大夫D.妇女不得参加任何事务

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