电气化铁路的输电线常用图所示的方式悬挂在钢缆上.钢缆的A端固定在电杆上,B端连接

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问题:

电气化铁路的输电线常用图所示的方式悬挂在钢缆上.钢缆的A端固定在电杆上,B端连接在滑轮组上.滑轮组由a、b、c三个滑轮构成,配重P由多个混凝土圆盘悬挂在一起组成,配重的总重为G,若不计摩擦和滑轮的重量,则以下说法中正确的是(  )

A.a为动滑轮,B端钢缆受到滑轮组的拉力大小约为3G

B.a为动滑轮,B端钢缆受到滑轮组的拉力大小约为G

C.a、c为动滑轮,B端钢缆受到滑轮组的拉力大小约为3G

D.a、c为动滑轮,B端钢缆受到滑轮组的拉力大小约为G

考点:定滑轮及其工作特点动滑轮及其工作特点
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我和小利是小学同学,小学时我们俩人的数学成绩不相上下,可升入初中后,我的数学成绩却远远地落在了小利后边,有几次测验,还不及格呢!我应该 (    )    

A.考试时请求小利帮助

B.及时调整自己的学习方法

C.主动和数学老师沟通

D.树立学好数学的自信心

题型:选择题

下列说法正确的是(  )

A.氢气燃烧时将化学能转化为热能

B.可燃物只要达到着火点就能燃烧

C.在鸡蛋清溶液中加入乙酸铅溶液发生的是物理变化

D.煤燃烧产生的二氧化碳是形成酸雨的主要原因

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联络地中海与大西洋的快捷方式是巴拿马运河?

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先天性腹股沟斜疝的主要发病机制是

A.腹内压升高

B.腹壁强度减弱

C.腹膜鞘状突未闭

D.腹壁缺损

E.先天性联合腱发育不全

题型:选择题

Regardless of their political affiliation, in all countries women must overcome a host of stumbling blocks that limit their political careers. "Most obstacles to progress consist of (1) of various kinds," says the Inter-Parliamentary Union (IPU), a Geneva-based organization (2) 139 parliaments, including the lack of time, training, information, self-confidence, money, support, motivation, women’s networks and solidarity between women.

In every culture, prejudice and stereotypes (3) hard. The belief still holds (4) that women belong in the kitchen and (5) the children, not at election (6) or in the Speaker’s chair. The media often reinforce traditional images of women, who, upon entering politics, also bear the brunt (正面冲击) of verbal and physical (7) .

In impoverished (贫穷的) countries (8) by civil conflicts and deteriorating economic and social conditions, women are (9) by the tasks of managing everyday life and looking after their families.

The IPU stresses the general lack of child-care facilities—often (10) a privileged few—the (11) of political parties to change the times and running of meetings and the weak backing women receive from their families. That support, which is (12) as well as financial, is (13) vital because women have internalized (14) images of themselves since the (15) of time and often suffer from low self-confidence.

Another obstacle is the lack of financial resources, especially as election campaigns become increasingly expensive. (16) , women encounter more or less open machismo (男子汉的高傲) in the (17) of closed political circles (18) entry to the "second sex. " Lastly, they (19) the lack of solidarity between women, (20) by the fact that the number of available positions is limited.

11()

A.endeavor

B.persistence

C.stubbornness

D.reluctance

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