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單項(xiàng)選擇題

A major health hazard of the product tert-butylamine is that it （）.

A.can be absorbed through the skin
B.causes irreversible damage to eye tissue
C.is a very unstable product
D.All of the above

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單項(xiàng)選擇題

A low pressure annular preventer which is used to direct flow of kick fluids away from the rig floor is called a （）.

A.dump valve
B.deflector
C.separator
D.diverter

單項(xiàng)選擇題

A low HDOP (Horizontal Dilution of Precision) number such as 2 indicates a （）.

A.poor fix
B.good fix
C.poor signal quality
D.good signal quality

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