一个圆的直径扩大4倍,它的周长扩大______倍,面积扩大______倍.
一个圆的直径扩大4倍,周长就扩大4倍,面积就扩大42=16倍.
故答案为:4,16.
As Chinese students, every day we have___________ homework to do and we are_________ tired.
A.too many; too much
B.many too ; much too
C.too much ; much too
D.much too ; too much
下面哪种练习方法属于重复练习法()。
A.以同一动作方式跳绳100次
B.连续爬山1小时
C.在公园里时跑时走
D.用蛙泳姿势和仰泳姿势连续慢游20分钟