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单选题
A well-lubricated bearing surface always appears（）
A
well knurled
B
slightly streaked
C
lightly glazed
D
highly polished
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observeB
investigateC
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look
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单选题_____from space, our earth, with water covering 70% of its surface, appears as a blue planet.A
SeeingB
To be seenC
SeenD
Having seen
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increase the trimB
change the free surface effectC
cause a serious listD
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单选题A serious loss of reserve buoyancy resulting from flooding any compartment of a ship will always（）.A
increase the trimB
change the free surface effectC
cause a serious listD
decrease ship stability
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