The magnification produced by a mirror is+1. What does it mean ?

The magnification product by a plane mirror is +1. What does it mean?

The magnification produced by a concave mirror is + 4. What does it mean ?

What does polymer mean?

Answer the following questions if the magnification of concave mirror = 1. What are the properties of an image ?

The magnification of the image by the concave mirror is -1. Mention the four characteristics of image from the above information.