Question

question b&c very fast its urgent​

Answer 1

I) The ability of a lens to converge or diverge light rays depends on its focal length.
II) Concave lens
III) P=1/f(in metre)
-2.5=1/f
1/-2.5
=-0.4m

Answer 2

power of lens is defined as the ability of a lens to converge or diverge the light

the spectacle gives virtual nd erect image and the focal length of the lens is negative

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