[$k = 1.38 \times {10^{ - 23}}J/K$]
[Given : $\mathrm{M}(\mathrm{Li})=6.01690\ \mathrm{amu} . \mathrm{M}\left({ }_1 \mathrm{H}^2\right)=2.01471 \ amu.$ $\mathrm{M}\left({ }_2 \mathrm{He}^4\right)=4.00388\ \mathrm{amu}$,$ and\ $$1 \ \mathrm{amu}=931.5$ $\mathrm{MeV}]$