Answer
$37.74$ $eV$
Work Step by Step
From the previous section of this problem, we have calculated the momentum of the electron: $p=3.315\times 10^{-24}$ $kg.m/s$
Now, the energy of an electron can be written as
$E=\frac{p^2}{2m}$,
where $m$ is the mass of the electron.
Thus, the energy of the electron is given by
$E=\frac{(3.315\times 10^{-24})^2}{2\times 9.1\times 10^{-31}}$ $J$
or, $E=\frac{(3.315\times 10^{-24})^2}{2\times 9.1\times 10^{-31}\times1.6\times 10^{-19}}$ $eV$
or, $E\approx 37.74$ $eV$
