A weak field complex of $\mathrm{N}{\mathrm{i}}^{2+}$ has magnetic moment of 2.82 BM. The number of electron in the ${\mathrm{t}}_{2\mathrm{g}}$ level of $\mathrm{N}{\mathrm{i}}^{2+}$ will be

Calculate the $\mathrm{EAN}$ of central atom in the following complex

$\left[\mathrm{Cr}{\left(\mathrm{CO}\right)}_6\right]$

Calculate the $\mathrm{EAN}$ of central atom in the following complex

${\left[\mathrm{Fe}(\mathrm{CN}{)}_6\right]}^{4-}$

Calculate the $\mathrm{EAN}$ of central atom in the following complex

$\left[\mathrm{Fe}(\mathrm{CO}{)}_5\right]$