What are the types of mirrors?

The focal length of a plane mirror is:

When a beam of light is incident on a plane mirror,it is found that a real image is formed. The incident beam must be

$A$ point object is kept in front of a plane mirror. The plane mirror is performing $SHM$ with an amplitude of $2 \ cm$. The plane mirror moves along the $x$-axis,and the $x$-axis is normal to the mirror. The amplitude of the mirror is such that the object is always in front of the mirror. The amplitude of the $SHM$ of the image is ....... $cm$.

Assertion : The image of a virtual object due to a plane mirror is real.
Reason : If the rays seem to be converging at a point behind a plane mirror,they are reflected and they actually meet in front of the mirror.

The angle made by the incident ray of light with the reflecting surface is called: