The binding energy of an electron in the ground state of $\mathrm{He}$ is equal to $24.6 \mathrm{eV}$. The energy required to remove both the electrons is

Binding energy per nucleon verses mass number curve for nuclei is shown in the figure. $W$, $X$, $Y$ and $Z$ are four nuclei indicated on the curve. The process that would release the energy is,

The energy of the reaction, ${\mathrm{Li}}^7+\mathrm{p} \text{(proton)}\stackrel{}{\to }2{\mathrm{He}}^4$ is,

(The binding energy per nucleon in ${\mathrm{Li}}^7$ and ${\mathrm{He}}^4$ nuclei are $5.60 \mathrm{MeV}$ and $7.06 \mathrm{MeV}$, respectively.)