Question

Please do these questions if anyone can .......​

Answer 1

2)What is normal? Normal is a line which is perpendicular to the reflecting surface.

If we assume that the concave / convex mirror as a whole sphere then the radius curvature becomes the normal for it as tangents are perpendicular to the radius at the point of contact like in the above picture

Since the incident Ray coincides with normal and forms 0° with the normal Hence by laws of reflection the reflected Ray is 0° and retraces the path of incident.