对水航速是船舶在（）情况下的对水航速。
Ⅰ．无风流；Ⅱ．有风无流；Ⅲ．有流无风；Ⅳ．有风流。
A．Ⅰ
B．Ⅰ～Ⅳ
C．Ⅰ，Ⅱ，Ⅳ
D．Ⅰ，Ⅱ
参考答案：B
某商品现价18元，亏了25%，亏了多少元？如果想赢利25%，应按多少元出售该商品？
The satellites over the major ocean regions cover the globe（）.
A.besides the polar regions
B.including the North Pole and the South Pole
C.above 70N and below 70S
D.as far north and south 70
