【单选题】
激光切割操作时，戴激光防护面罩主要是用于防___
A. 红外激光
B. 可见光
C. 紫外激光
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答案
C
解析
暂无解析
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关于二氧化碳焊短路过渡焊接以下说法错误的是___。
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可能引起管道发生燃烧爆炸的行为是___。
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焊接作业发生火灾逃生时,要尽量贴近地面撤离,主要原因是___
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【单选题】
1___
A. She is going to have a lot of vanilla icecream.
B. She won the pelling competition at her school.
C. She is going to the state capital for a competition.
D. She spelled“exellence" correctly, but others didn't.
【单选题】
2___
A. His family moved to Sacramento to settle down.
B. His family bought him a new suit and a new tie.
C. He went to Sacramento for a spelling competition.
D. He won the first prize in the state spelling competition.
【单选题】
3___
A. Tomake him feel better after he lost the first prize.
B. To apologize for not buying him some ice cream.
C. To wish him good luck in the next competition.
D. To congratulate him on winning the frst prize.
【单选题】
1___
A. Superstitions and science.
B. Tips on how to have good luck.
C. Superstitions in the United States.
D. Rational and superstitious societies.
【单选题】
2___
A. Walking under a ladder.
B. Dreaming of a black cat.
C. Hanging a mirror in the house.
D. Stepping on one's own shadow.
【单选题】
3___
A. Because black cats look like witches.
B. Because black cats were thought to be witches.
C. Because black cats bring seven years of bad luck.
D. Because black cats are hard to notice in darkness.
【单选题】
4___
A. Breaking a mirror on purpose.
B. Catching a falling leaf on one's birthday.
C. Finding a penny on the ground and picking it up.
D. Dreaming of blowing out the candles in one blow.
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1___
A. Read J. K. Rowling's first book.
B. Go to buy a new Harry Potter book.
C. Watch BBC news about J. K. Rowling.
D. Take her cousin to see a new Harry Potter movie.
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3___
A. She won't write any more books.
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4___
A. J. K. Rowling's secret.
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1___
A. He broke the milk bottle.
B. He fell down on the floor.
C. He made a mess inside the refrigerator.
D. He spilled the milk over the kichcn floor.
【单选题】
2___
A. Ѕhе gаvе hіm а lоng leсture.
B. She shouted at him in anger.
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【单选题】
3___
A. How to do an experiment.
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D. How to avoid making mistakes.
【单选题】
4___
A. Mistakes can become learning opportunities.
B. Mistakes are just like scientific experiments.
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【单选题】
1___
A. Because he likes the sunny weather,
B. Because he wants to challenge himself.
C. Because it can help solve his sleeping problem.
D. Because it can help him forget all his troubles.
【单选题】
2___
A. To go sailing.
B. To go surfing.
C. To go to the beach.
D. To go to her nephew's.
【单选题】
3___
A. Going to visit relatives.
B. Enjoying the warm sun on the beach.
C. Building sand castles with her niece and nephew.
D. Playing in the sand and jumping in the waves.
【单选题】
4___
A. Surfing in the sea.
B. Collecting seashells.
C. Building sand castles.
D. Jumping in thewaves.
【单选题】
2___
A. People aged 16to 24.
B. People aged 25 to 34.
C. People aged 16 and over.
D. People aged 55 and over.
【单选题】
3___
A. People aged16 to 24 preferred listening to music most.
B. more popularB It was geting more andamong the Bish people.
C. Trwas the third most popular ativity among people aged 55 and over.
D. People aged 25 to 34 listened to musicmore often than those aged 16 to 24.
【单选题】
4___
A. Older people go out to pubs more often.
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C. Older people spend more time reading and gardening.
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【单选题】
3___
A. She can either read or rest a little on the train.
B. She can read and respond to emails on the train.
C. She can travel to many different parts of the city.
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【单选题】
4___
A. He can take the train to the old part of the city.
B. He can save a lot of money when he takes the train.
C. He can save 20 minutes to go to work with the train.
D. Hecan take the train to the airpor insted of driving.
【单选题】
1___
A. About an hour.
B. More than an hour.
C. About half an hour.
D. More than one and a half hours.
【单选题】
2___
A. More and more Americans spend over an hour getting to work.
B. Over 10 percent of Americans spend less than an hour getting to work.
C. Only New York people spend more than 90 minutes getting to work.
D. Over 10 percent of Americans spend more than 90 minutes getting to work.
【单选题】
3___
A. Because gas prices are not high.
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C. Because he can attend a better school.
D. Because he can have his favorite lifestyle.
【单选题】
4___
A. Traffic jams.
B. Expensive housing.
C. Poorer life quality.
D. A tiring and boring trip.
【单选题】
1___
A. She liked playing an interesting game.
B. She enjoyed seeing many of her old friends.
C. She enjoyed wearing her Halloween costume.
D. She liked the decorations in Jason's front yard.
【单选题】
2___
A. None of her friends likes Jason.
B. None of Jason's guests is young.
C. She wants to go to Linda's party.
D. She went to Jason's party last year.
【单选题】
3___
A. The party will last four hours.
B. Six people will attend the party.
C. They will have huge bags of candy.
D. They will play a new game called Guess Who"
