题目

When ______ at the ticket office, my brother and I found we didn't have enough money to buy tickets for ______ of us. A．arrived; the two    B．arrived; two    C．arriving; the two    D．arriving; two   答案：C如图所示是关于小猫和小聪的一幅漫画，图中两条光线的夹角是60°，则小聪观察小猫光路的入射角是________度，此现象说明在反射时，光路是________．