A spherical drop of liquid splits into 1000 identical spherical drops. If$\mathrm{u}_{\mathrm{i}}$ is the surface energy of the original drop and $\mathrm{U}_{\mathrm{f}}$ is the total surface energy of the resulting drops, the (ignoring evaporation).$\frac{u_f}{u_i}=\left(\frac{10}{x}\right)$. . Then value of x is