The work done in placing a charge of $\;8\times10^{-18}\;$ coulomb on a condenser of capacity 100 micro-farad is

Question

$(a)\;16\times10^{-32}\;J\qquad(b)\;31\times10^{-26}\;J\qquad(c)\;4\times10^{-10}\;J\qquad(d)\;32\times10^{-32}\;J$