某地的纬度为0度,经度为0度,那么该地所处的温度带是[ ]
A.热带
B.北温带
C.寒带
D.温带
答案:A
什么是水的硬度?硬度可分为几类?它的常用单位是什么?
A ship is inclined at an angle of loll. In the absence of external forces,the righting arm (GZ) is().
A.positive
B.negative
C.zero
D.vertical