A:She is to blame
B:That’s impossible
C:It doesn’t matter
D:That’s too bad
30÷6=____ 24÷4=____ 3×6=____ 4×2=____
2×5=____ 6×3=____ 18÷3=____ 3×2=____
已知函数f(x)=log3x,x>02x,x≤0,则ff(19)的值为____