A means a holiday, and people can do whatever they like during the holiday.
A:seat
B:vacation
C:festival
下列不属于单细胞生物的是( )
一台显微镜目镜与物镜放大倍数的乘积就是该显微镜的放大倍数.(判断对错)
已知fx是定义域为R的奇函数, f-4=-1,fx的导函数f'x的图象如图所示, 若两正数a,b满足fa+2b<1,则a+2b+2的取值范围是( )