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單項選擇題

What will NOT increase friction of a liquid flowing in a pipe and cause a loss of suction head?（）.

A.Bends in the piping
B.Slowing the pumping rate
C.Pipeline valves
D.Backing rings for pipe welds

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單項選擇題

What normally helps in detecting escaping gas? （）

A.Running hand along pipe
B.Red flame
C.Odor
D.Increase the line pressure

單項選擇題

What is used to test a tank for oxygen content?（）

A.Combustible gas indicator
B.Vapor indicator
C.Atmosphere analyzer kit
D.None of the above

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