A:人口出生率高
B:人口死亡率低
C:人口基数大
D:自然增长率高
列竖式计算。
①67×21= ②34×84= ③85×20=
④77×23= ⑤45×30= ⑥46×33=
The book was written in ______easy English ______even primary school students could understand it.
第三次印巴战争后,南亚次大陆的政治天平明显向印度倾斜,理由是( )
用手将一重为5N的物体全部压入水中,物体排开的水重8N,此时物体受到的浮力为____N,放手后物体将____ (填“上浮”或“下沉”),待物体静止时所受浮力为____N.