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單項(xiàng)選擇題

A marine chemist issues gas free certificates and is certified by which organization? （）

A.Mine Safety Appliance Association
B.American Chemical Society
C.Marine Chemists Association
D.National Fire Protection Association

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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

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

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