What happens when a soap bubble is charged?

The work done in splitting a drop of water of $1\, mm$ radius into $10^6$ droplets is (surface tension of water $T = 72 \times 10^{-3}\, N/m$):

In air,a charged soap bubble of radius $R$ breaks into $64$ small soap bubbles of equal radius $r$. The ratio of mechanical force per unit area of the big soap bubble to that of a small bubble is

$A$ water drop is divided into $8$ equal droplets. The pressure difference between the inner and outer side of the big drop will be

$A$ spherical drop of oil of radius $1\, cm$ is broken into $1000$ droplets of equal radii. If the surface tension of oil is $50\, dynes/cm$,the work done is

If two soap bubbles of equal radii $r$ coalesce,then the radius of curvature of the interface between the two bubbles will be: