The boy is only . Today is his birthday.
A:five; five
B:fifth; five
C:fifth; fifth
D:five; fifth
一艘潜水艇潜入水面以下100m深度时,潜水艇的舱盖(面积2m2)所受到水的压强和压力各是多少?
逆城市化是城市化的倒退.(判断对错)
在0,﹣2,1,﹣3这四个数中,最小的是( )