What is the focal length of a plane mirror?

What is the absolute refractive index of water?

$A$ child is standing in front of a magic mirror. She finds the image of her head bigger, the middle portion of her body of the same size, and that of the legs smaller. What is the order of combinations for the magic mirror from the top?

Which type of mirror can produce a virtual image?

$A$ ray of light is incident on a concave mirror after passing through the centre of curvature. What is the angle of incidence (in $°$)?

Draw a ray diagram showing the path of rays of light when it enters with oblique incidence: $(i)$ from air into water; $(ii)$ from water into air.