What is the $EAN$ of $Fe$ in $[Fe(CN)_6]^{3-}$?

During the race of complex compounds,the finish line is fixed by achieving an $E.A.N.$ value equal to the atomic number of the corresponding inert gas. Which of the following complexes is present at the finish line?

What is the Effective Atomic Number $(EAN)$ of Cobalt in $[Co(NH_3)_6]Cl_3$ (Atomic number of $Co = 27$)?

The complex that violates the Sidgwick's rule of $EAN$ is

The $EAN$ of $Ni$ in $[Ni(CO)_4]$ is ....

If $E.A.N.$ of central metal cation $M^{2+}$ in a non-chelating complex is $36$ and atomic number of metal $M$ is $26$,then the number of monodentate ligands in this complex are