小明在教室里看到挂在墙上的镜子时想到：

（1）光在镜面上发生反射时，反射角________入射角。

（2）教室黑板发生“反光”现象，这是因为黑板太光滑，发生了__________造成的。

（3）物体能在平面镜中成像。小明说：“物体在平面镜中成的像到平面镜的距离等于物体到平面镜的距离”。你能用实验证明上述说法是正确的吗？请简述你的实验过程。

– What were you doing when I called you last night?

– I ______ my homework and was going to bed.

A. did                      B. had done             C. was doing