—I am sorry to hear that.
A:as many as
B:less than
C:more than
3×5=____
7÷1=____
4×8=____
63÷9=____
6×8=____
6×6=____
给出如下结论:
①对任意m∈Z,有f(2m)=0;
②函数f(x)的值域为0,+∞);
③存在n∈Z,使得f(2n+1)=9;
正确的有( )
由2氯丙烷制取少量的1,2丙二醇时,需要经过下列哪几步反应?( )