Three concentric spherical metallic shells `A, B, and C` of radii `a,b, and c(a lt b lt c)` have surface charge densities `sigma, -sigma` and `sigma`, respectively.
If `V_(A), V_(B)` and `V_(C)` are potential of shells A, B and C, respectively, match the columns
`{:("Column A",,,"Column B"),(a. V_(A),,i.,sigma/epsilon_(0)[(a^(2)-b^(2)+c^(2))/c]),(b. V_(B),,ii.,sigma^(2)/epsilon_(0)[a^(2)/b-b+c]),(c. V_(C),,iii.,sigma/epsilon_(0)[a-b+c]):}`

Explanation

`a. rarr iii., b. rarr ii., c. rarr i., 21. b.`