A square object of area 100 cm^2 is placed perpendicular to the principal axis of a concave mirror.If the lateral magnification of the mirror for the above object position is 0.4 then the area of image will be a)16 cm^2 b)40cm^2 c)100cm^2 d)250cm^2 given ans is d...sir how???

When a square object of area 100 sq.
Cm is placed perpendicular to the principal axis of a concave mirror with a lateral magnification of the mirror, for the above object position is 0.4, and then the area of the image will be perpendicular to the central axis of the concave mirror.