To get three images of a single object, one should have two plane mirrors at an angle of $...^\circ$.

$A$ ray reflected successively from two plane mirrors inclined at a certain angle undergoes a deviation of $300^o$. The number of observable images is:

The figure shows a cubical room $ABCD$ with the wall $CD$ as a plane mirror. Each side of the room is $3\,m$. $A$ camera is placed at the midpoint of the wall $AB$. At what distance should the camera be focused to photograph an object placed at $A$?

$A$ plane mirror produces a magnification of

When a plane mirror is placed horizontally on a level ground at a distance of $60 \ m$ from the foot of a tower,the top of the tower and its image in the mirror subtend an angle of $90^\circ$ at the eye. The height of the tower will be.....$m$.

What should be the angle between two plane mirrors so that whatever be the angle of incidence,the incident ray and the reflected ray from the two mirrors are parallel to each other (in $^o$)?