【判断题】
>常用的交流无触点开关，其内部实际上是两只晶闸管的正向并联
A. 对
B. 错
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答案
B
解析
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相关试题
【判断题】
>“五同时”是指企业生产(经营)的领导者和组织者，必须明确安全与生产是一个有机的整体，要将安全与生产的产量(进度)一起抓，在生产工作的时候，同时计划、布置、安排、检查、总结、评比安全工作
A. 对
B. 错
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【单选题】
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A. Last year .
B. In college .
C. Last week .
D. In high school .
【单选题】
Q3: How does the man feel about running?___
A. Boring.
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A. Because she fears that a big fish might eat her .
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A. 1:3.
B. 3 :1.
C. 1 :10 .
D. 10 :1.
【单选题】
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A. It improves relationships .
B. It leads to greater success .
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【单选题】
Q3: What does the speaker say about negative feelings?___
A. People should turn every negative feeling around .
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【单选题】
Q4: What is the main idea of the passage?___
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【单选题】
Q1: What are the man and woman talking about?___
A. Whether nature is magical and kind .
B. Whether nature is powerful and full of risks .
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【单选题】
Q2: What can we learn about Christopher?___
A. He made a film about his trip to Alaska .
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【单选题】
Q3: What does the woman think about Christopher taking the trip to Alaska?___
A. He was too foolish .
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【单选题】
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【单选题】
Q1: What speed can an avalanche reach within five seconds of taking off?___
A. At 8 miles an hour .
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【单选题】
Q2: According to the passage, under what circumstances may an avalanche occur?___
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【单选题】
Q3: What are skiers advised to do to avoid being caught in an avalanche?___
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【单选题】
Q4: Why does the ski patrol use explosives?___
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【单选题】
Q1:What is conversation mainly about?___
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【单选题】
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【单选题】
Q3:Where did the woman get the money?___
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【单选题】
Q2: According to Rubin, what can small companies do to thank holiday workers?___
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【单选题】
Q3: What can small business owners do to help holiday workers get into the holiday spirit?___
A. Entertain them with big meals .
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【单选题】
Q4: Who are supposed to benefit most from this passage?___
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【单选题】
In the first two paragraphs of the passage the writer tries to tell us that___
A. he had lived in Washington D.C. for twenty years
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【单选题】
The writer ,as a child ,was very fond of playing in the basement because ___
A. it was bright and alive
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【单选题】
How did the writer feel when he visited his old neighborhood in Washington D.C. ?___
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【单选题】
On his visit to his hometown ,the writer found the old apartment building___
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【单选题】
" Youcan never go home again "inthe last sentence of this passage means that___
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【单选题】
We learn from the passage that Tracy died___
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【单选题】
Tracy's parents decided to donate Tracy's organs because___
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【单选题】
The meeting between the writer's family and Tracy's parents was arranged because___
A. the writer and her husband wished to express their thanks to Tracy's parents
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【单选题】
The writer and her husband learned how Tracy died___
A. from his parents
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【单选题】
The meeting between the two families helped to ease the Marshes'suffering because___
A. they saw that David looked very much like their son
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【单选题】
The writer's first marriage was unsuccessful because___
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【单选题】
When the writer asked for a divorce ,her husband___
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【单选题】
When the writer first met Clint ,she felt that___
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【单选题】
The writer was particularly touched by Clint because___
A. he loved her children and asked for their approval of the marriage
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【单选题】
The writer's marriage to Clint is important to her mainly because___
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【单选题】
What was Goodall's childhood dream ?___
A. She dreamed of going to college .
B. She dreamed of studying animals in Africa .
C. She dreamed of becoming a scientist .
D. She dreamed of traveling all around the world .
【单选题】
What did Goodall's mother think of her dream ?___
A. As a girl she should not go to the African jungle .
B. Her dream would remain a dream unless she got the right training .
C. As a girl she should stay away from violent animals .
D. She could make her dream come true if she was determined .
