What type of image is formed by a plane mirror?

The distance between the object kept at $2 \, m$ from a plane mirror and its image is $.....$ (in $, m$)

Which type of image cannot be obtained by a concave mirror?

An object $3.0 \text{ cm}$ high is placed perpendicular to the principal axis of a concave lens of focal length $7.5 \text{ cm}$. The image is formed at a distance of $5.0 \text{ cm}$ from the lens. Calculate $(i)$ distance at which object is placed,and $(ii)$ size and nature of image formed.

$A$ plane mirror produces a magnification of

An incident ray falls normally on a glass slab. What is the angle of refraction (in $°$)?