According to Slater's rule, which of the following has correct order of  ${\mathrm{Z}}_{\mathrm{eff}}$?

For Li,

$\begin{array}{l}s=1.7\\ z=3\\ \mathit{\Rightarrow }{z}_{\text{eff }}=3-1.7\\ =1.3\end{array}$

For Na,

$\begin{array}{l}s=8.8\\ z=11\\ \mathit{\Rightarrow }{z}_{\text{eff }}=11-8.8\\ =2.2\end{array}$

For Be the value of effective nuclear charge is 1.95 and for Mg it is 2.85.