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问题 单项选择题

某220kV变电所建于平原地区，污秽等级为Ⅲ级，220kV采用双母线接线，主变压器的变比为220/115±8×1.25%/10.5kV，接线组别为YNynOd11。

通过计算，确定变电所内220kV电压等级悬垂绝缘子串的片数为( )，悬式绝缘子采用XWP-100，爬距为450mm，其爬距有效系数为0.95。

A．14片；
B．15片；
C．16片；
D．17片。

答案

参考答案：C

解析： 根据《高压架空线路和发电厂、变电所环境污区分级及外绝缘选择标准》(GB/T16434-1996)表2，Ⅲ级污秽的爬电比距为25mm/kV，最高工作电压为252kV，故爬距应为6300mm。悬垂绝缘子串的片数为m=6300/(0.95×450)=14.7，取15片，再加1片零值绝缘子，即16片。

马克思主义是关于全世界无产阶级和全人类彻底解放的科学理论。其诞生的标志是

A． * * 运动的开始

B．巴黎公社革命爆发

C．《 * * 党宣言》发表

D．《国际歌》的诞生
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填空题

Part 3


Questions 19-25


·Read the following passage and answer questions 19-25.
·For questions 19-25, choose the correct answer A, B, C and D.
·Mark your answers on the Answer Sheet.
While still in its early stages, welfare reform has already been judged a great success in many states, at least UN is getting people off welfare, lt’s estimated that more than two million have left the roles since 1994.
In the past four years, welfare in rolls in Athens country has been cut in half. But 70 percent of the people who left in the past two years took jobs that paid less than $6 an hour. The result: The Athens country poverty rate still remains at more than 30 percent—twice the national average.
For advocates for the poor, that’s an indication that much more needs to be done.
"More people are getting jobs, but it’s not making their lives any better," says Kathy Lairn, a policy analyst at the center in budget and policy priorities in Washington.
Canter analysis of US census data nationwide found that between 1995 and 1996, a great percentage of single, fame-headed household were earning money on their own, but that average income for these households actually went down.
But for many, the fact that poor people are able to support themselves almost as well without government aid as they did with it is in itself a huge victory.
"Welfare was a poison. It was a toxin that was poisoning the family," says Rector, a welfare reform is changing the moral climate in low-income communities. It’s beginning to rebuild the work ethic, which is much more important.
Mr. Rector and others argued that once "the habit of dependency is cracked," then the country can make other policy changes aimed at improving living standards.

Why aren’t people enjoying better lives when they have jobs

A．Because their wages are low.

B．Because many families are divorced.

C．Because the cost of living is rising.

D．Because government aid is now rar
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