Question

yor are provided with 3 mirrors ( concave, convex and plane ) without touching them how can u find their nature

Answer 1

in a plane mirror you will get same size image
in a concave mirror you will get magnified image
in a convex mirror you will get diminished image

Answer 2

you have to either look in the mirror yourself or place a candle in front of the mirror. if you get an erect and same sized image , its a plane mirror. if the object is placed very close to the mirror and if it looks enlarged then its probably a concave mirror. then automatically the third mirror would be a convex mirror