A water drop of radius \( 1 \, \text{cm} \) is broken into \( 729 \) equal droplets. If surface tension of water is \( 75 \, \text{dyne}/\text{cm} \), then the gain in surface energy upto first decimal place will be:(Given \( \pi = 3.14 \))
\( 8.5 \times 10^{-4} \, \text{J} \)
\( 8.2 \times 10^{-4} \, \text{J} \)
\( 7.5 \times 10^{-4} \, \text{J} \)
\( 5.3 \times 10^{-4} \, \text{J} \)
