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.

The magnetic moment of $Cr$ in $[Cr(H_2O)_6]Cl_3$ is $3.88 \, BM$. Which of the following is the possible orbital distribution for $Cr$?

Give the correct sequence of initials $T$ or $F$ for the following statements. Use $T$ if the statement is true and $F$ if it is false.
$(I) \ Co(III)$ is stabilized in the presence of weak field ligands,while $Co(II)$ is stabilized in the presence of strong field ligands.
$(II)$ Four-coordinated complexes of $Pd(II)$ and $Pt(II)$ are diamagnetic and square planar.
$(III) \ [Ni(CN)_4]^{4-}$ ion and $[Ni(CO)_4]$ are diamagnetic tetrahedral and square planar respectively.
$(IV) \ Ni^{2+}$ ion does not form inner orbital octahedral complexes.

Both $[Ni(CO)_4]$ and $[Ni(CN)_4]^{2-}$ are diamagnetic. The types of hybridisation of $Ni$ in these complexes are . . . . . . and . . . . . . respectively.

For the complexes showing the square pyramidal structure,the $d-$orbital involved in the hybridisation is

The structure of iron pentacarbonyl,$Fe(CO)_5$,is ................. .