单项选择题
A.low steel on the Huey P. Long Bridge B.mean sea level C.the local water table D.the minimum dam control level
Most drill ships and barges have a walled opening below...
单项选择题Most drill ships and barges have a walled opening below the derrick，open to the water’s surface and through which various drilling tools can pass down to the sea floor called a （）.
A.moon pool B.spider deck opening C.pontoon D.keyway
Most covered lifeboats will right themselves after caps...
单项选择题Most covered lifeboats will right themselves after capsizing if the（）.
A.lower ballast tanks are filled with water B.sea anchor is deployed to windward C.fuel tanks are not less than half full D.passengers are strapped to their seats
Mean low water is the average height of（）.A.the surface...
单项选择题Mean low water is the average height of（）.
A.the surface of the sea B.high waters and low waters C.all low waters D.the lower of the two daily low tides
