Consider the ground states ($n=1$) of $\mathrm{H}$, $\mathrm{He}{}^{+}$ and $\mathrm{Li}{}^{2+}$ in the Bohr model. Select the correct statements.

1. AThe ground-state energy of $\mathrm{Li}{}^{2+}$ is three times that of $\mathrm{H}$
2. BThe radius of the ground-state orbit of $\mathrm{Li}{}^{2+}$ is one third that of $\mathrm{H}$
3. CThe ionisation energy of $\mathrm{He}{}^{+}$ is four times that of $\mathrm{H}$
4. DThe electron in $\mathrm{Li}{}^{2+}$ moves three times as fast as in $\mathrm{H}$