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【单选题】
关于闪光对焊,下列说法正确的是( )。A.
对导电性和导热性好的金属进行闪光对焊时，应采用较小的闪光速度和较长的焊接时间
B.
对强度高的金属进行闪光对焊时，应采用较小的顶锻压力
C.
淬火钢通常采用加热区窄的预热闪光对焊
D.
铝合金闪光对焊时，必须采用很高的闪光和顶锻速度、大的顶锻留量和强迫形式的顶锻 模式
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【单选题】Why did Jack say he needed some time to spend with his son?
A.
Because he was very tired of his work and wanted to have a good rest.
B.
Because he had promised to spare more time to stay with his son.
C.
Because he had missed his son and his family for days.
D.
Because he came to realize the importance of the time with his family.
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A.
Because of the mood;
B.
Because he used to long to play with the blacks.
C.
Because he wanted Pecola to play cat together.
D.
Because Junior is the son of a brown and the white kids didn ’ t play with him either.
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A.
Because he wanted to let the mother remember him.
B.
Because he wanted people to know he was the president.
C.
Because he wanted to show his thanks and kindness to the mother.
D.
Because he wanted to encourage the young soldier.
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A.
to let the mother remember him
B.
people to know he was the president
C.
to show his thanks and kindness to the mother
D.
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A.
To sign up his son for the event
B.
To share her volunteer experience
C.
To offer to help
D.
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