Why are convex mirrors commonly used as rear - view mirrors in vehicles?

(a) Why does a ray of light passing through the centreofcurvature of a concave mirror after reflection is reflected back along the same path ?
(b) Why are convex mirrors commonly used as rear - view mirrors in vehicles?
© A pencil partly immersed in water in a glass tumbler appears to be displaced at the interface of air and water. Name the phenomenon of light responsible for it.

(a) Because the incident ray falls on the mirror along the normal to the reflecting surface.
(b) Because they always give an erect, though diminished image. Thus, convex mirrors enable the driver to view much larger area.
© Refraction of light.