单项选择题
A tank which has been sealed for a long period of time can be dangerous because （）.
A.steel surfaces consume oxygen by rusting
B.sealed tanks usually form a vacuum
C.moisture condenses in the tank, displacing the oxygen
D.most tank coatings give off poisonous vapors in the presence of moisture
相关考题
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单项选择题
Records of garbage disposal are required to be maintained （）.
A.until each quadrennial PSC inspection
B.until the end of each voyage
C.for a minimum of one year
D.for a minimum of two years -
单项选择题
The use of sinking and dispersing agents for the removal of surface oil is （）.
A.the most common method used in the United States
B.too expensive for common use
C.generally safe to sea life
D.generally harmful to sea life -
单项选择题
One of the disadvantages of using carbon dioxide to extinguish a fire in an enclosed space is （）.
A.the "snow" which is sometimes discharged along with the gas is toxic
B.prolonged exposure to high concentrations of C02 gas causes suffocation
C.rapid dissipation of the C02 vapor
D.the C02 gas is lighter than air and a large amount is required to extinguisha fire near the deck
