A piece of cloud is having area $25\times {10}^6 {\mathrm{m}}^2$ and electric potential of $10^{5}$ $\mathrm{V}$. If the height of cloud is $0.75 \mathrm{km}$, the energy of electric field between earth and cloud will be,

A battery is used to charge a parallel plate capacitor till the potential difference between the plates becomes equal to the electromotive force of the battery. The ratio of the energy stored in the capacitor and the work done by the battery will be