Given, a convex mirror,

u = -20 cm ; f = 30cm

By mirror formula, 1/f = 1/v + 1/u,

we get v = +12 cm

Height of object = 3 cm

Let height of image = *x*

*-v/u = x/3*

-12/20 = *x*/3

x = 9/5

Therefore, position of object is 12 cm (behind the mirror)

Nature of object is virtual

Size of object = 9/5 cm

__This solution is strictly for practice purposes, do not use it during examinations.__