Passenger side mirrors were optional. Some were mechanically (not powered) remote controlled.
Side view mirrors.
To give a wider angle of view.
The proper side view mirrors for your 71 are 71-73 same model and were remote control. 74-78 used a different mirror.
They use convex mirrors to give a wider view.
adjusting your rear view and side mirrors properly Edit: Or Installing large side mirrors
Called side mirrors. Drivers side mirror/passenger side mirror.
Yes
The side view mirrors can be heated for removing ice/snow.
On what?
Concave mirrors are used in telescopes. Convex mirrors are used as side-view mirrors in cars.
Side view mirrors, or known as wing mirrors, are used to help the driver see the traffic behind their vehicle, in the blind spot. They are normally placed on the exterior of cars.
Convex mirrors diverge light rays, resulting in a virtual upright image that is smaller than the object. They have a wider field of view than concave mirrors and are commonly used in vehicle side view mirrors to provide a wider view of the surroundings.