In the tetrahedral complex $K_2[NiCl_4]$,what is the number of electrons present in the $3d$ orbital of the central metal ion?

Match the List-$I$ with List-$II$

List-$I$ (Molecules/ion)	List-$II$ (Hybridisation of central atom)
$A. PF_5$	$I. dsp^2$
$B. SF_6$	$II. sp^3d$
$C. Ni(CO)_4$	$III. sp^3d^2$
$D. [PtCl_4]^{2-}$	$IV. sp^3$

Choose the correct answer from the options given below $:$

Which of the following statements are true about $[CoF_6]^{3-}$ ion?
$I$. The complex has octahedral geometry.
$II$. Coordination number of $Co$ is $3$ and oxidation state is $+6$.
$III$. The complex is $sp^3d^2$ hybridised.
$IV$. It is a high spin complex.

$d^{2}sp^{3}$ hybridisation of the atomic orbitals gives

Which of the following complexes does not match with the hybridization state of its metal ion?
$(i) [Ni(CO)_4], sp^3$
$(ii) [Ni(CN)_4]^{2-}, sp^3$
$(iii) [CoF_6]^{3-}, d^2sp^3$
$(iv) [Fe(CN)_6]^{3-}, sp^3d^2$

Which of the following statements about $Fe(CO)_5$ is correct?