Which of these types of mirrors are used as rear view mirrors?

Q. Out of plane mirror, convex mirror and concave mirror:
(a) Which mirror is used as a reflector in the headlights of a car?
(b) Which mirror is used as a rear-view mirror in a car?

Q. Convex mirrors are used as rear-view mirrors, as they have a wider field of view.

Q. What kind or mirror will you use as a rear view mirror in a car–convex or concave? Why?

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