What is the $EAN$ of nickel in $Ni(CO)_4$?

What is the value of the effective atomic number $(EAN)$ of cobalt in the $[Co(NH_3)_6]^{3+}$ complex,given that the atomic number of $Co$ is $Z=27$?

What is the $EAN$ (Effective Atomic Number) of the metal ion in the hexacyanoferrate$(II)$ ion?

The $EAN$ of platinum in potassium hexachloroplatinate $(IV)$ is :

What is the Effective Atomic Number $(EAN)$ of $Co$ in $[Co(NH_3)_6]^{3+}$?

What is the effective atomic number $(EAN)$ of $Zn$ in $[Zn(NH_3)_4]SO_4$? (Atomic number of $Zn = 30$)