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單項選擇題

A facility used for the discharge of a cargo of a particular hazard,such as chlorine,butane or ethane,must have what to warn water traffic of an immediate danger during fire or cargo release?()

A.An emergency boat and crew
B.A siren or rotating flashing light
C.Flashing red lights located one-half mile upstream and downstream of the facility
D.Buoys with flashing lights controlled from shore,located one-half mile upstream anddownstream of the facility

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