The energy released when $1000$ small drops each of radius $10^{-7}\;m$ coalesce to from a single big drop is (Surface tension of liquid is $14 \times 10^{-2}\;N/m$)

Question

\[\begin {array} {1 1} (a)\;7.9 \times 10^{12}\;J \\ (b)\;1.58 \times 10^{-11}\;J \\ (c)\;7.9 \times 10^{-11}\;J \\ (d)\;1.58 \times 10^{-12}\;J \end {array}\]