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單項選擇題

Corrosive liquids and acids should have which kind of label?（）

A.Skull and crossbones
B.Yellow and white
C.Red and white
D.White and black

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單項選擇題

Conventional anchors are least likely to hold in a bottom consisting of（）.

A.soft clay
B.hard mud
C.very soft mud
D.sand

單項選擇題

Control of fire should be addressed（）.

A.immediately after restoring vital services
B.immediately
C.following control of flooding
D.following establishment of fire boundaries