A:These children are playing football.
B:The child is playing football.
一个数既是40的因数,又是4的倍数,这个自然数不可能是( )
已知等腰三角形的一边长等于4cm,另一边长等于9cm,则此三角形的周长为 ____cm.
It is reported that after lengthy talks the two sides finally reached a c____.