Lets say radius of small droplets is r and that of big drop is R. Total volume of the drops will remains unchanged. Therefore,
34πR3=1000(34πr3)
⇒R=10r
Now, initial surface energy is, Ui=1000(4πr2S) and the final surface energy is,
Uf=4πR2S
=100(4πr2S)
Clearly, Uf=101Ui.