单选题The（）should ensure that the holds in which chemical packages are stowed are properly supervised during the loading operations and these packages are regularly inspected for leakage or damage on the voyage.A berth operatorB harbour supervisorC master of

Which statement about entering into a tank which has been sealed for a long time is TRUE ________．

A.The tank should be tested only once to ensure the oxygen content is at least 14% before entry

B.The tank must be tested at frequent intervals to ensure that hazardous gasses have not regenerated

C.The tank need not be tested for oxygen content if it is ventilated for more than 24 hours

D.If the oxygen content tests at less than 12% you should wear an approved gas mask

______, as the chemical extinguisher agent, should be used for an electric fire.

A.dry chemical or foam

B.foam or soda acid

C.carbon dioxide or foam

D.carbon dioxide or dry chemical

A. Hub

B. Router

C. Switch

D. Firewall

Which statement concerning the application of dry chemical powder is FALSE ________．

A.At temperatures of less than 32℉，the extinguisher must be recharged more often

B.When possible，the fire should be attacked from windward

C.The stream should be directed at the base of the fire

D.Directing the stream into burning flammable liquid may cause splashing

All the holds and other parts of the ship in which cargo is to be stowed should be ______ for the carriage.

A.comfortable

B.suitable

C.stable

D.Favorable

A. Daily

B. Incremental

C. Normal

D. Differential