(20 10? Nanjing) As shown in the figure, a beam of light is reflected and refracted at the interface between air and glass, where _ _ _ _ is the refracted light.

Solution: According to the fact that the included angle between reflected light, incident light and normal is equal,

Therefore, one of EO and OC is incident light and the other is reflected light, and GD in the figure is normal;

According to the fact that refracted light and incident light are on both sides of the normal and in two media,

So OA and EO are incident light and refracted light, and BF is the interface in the figure;

In short, EO must be incident light, OC is reflected light, and OA is refracted light, as shown in the figure:

So the reflection angle ∠ doc = 40.

So the answer is: OA, 40