单项选择题
A.Skull and crossbones B.Yellow and white C.Red and white D.White and black
Conventional anchors are least likely to hold in a bott...
单项选择题Conventional anchors are least likely to hold in a bottom consisting of（）.
A.soft clay B.hard mud C.very soft mud D.sand
Control of fire should be addressed（）.A.immediately aft...
单项选择题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
Considering the general circulation of the atmosphere，t...
单项选择题Considering the general circulation of the atmosphere，the wind system between latitudes 30°N and 60°N is commonly called the（）.
A.prevailing westerlies B.horse latitudes C.trade winds D.subpolar low pressure belts
