Answer 1

Let r₂ be the angle of reflection from the second mirror. 

From laws of reflection,

`angle i _1 = angle r_1 = 30° `

Now in `triangle` ABC

θ = 180° - 90° - 60° = 30°

⇒ i₂ = 60°

Hence , r₂ = 60°

The angle of reflection of incident ray is 60^∘.