回复：谢谢诸位！第二题答案是E，但我还是不甚明白，烦请再说细点。

21, k=-2 is obvious, since the whole graph shifts down by 2. To determine h is a little tricky. Think when x=2, g(x) = f(x+h)-2=f(2+h)-2=1, so f(2+h)=3, the same as f(-1). So 2+h=-1, h=-3