Which one has the highest paramagnetism?

Compound	Total stereoisomers
$A$. $[Co(en)_2Cl_2]^+$	$P$. $2$
$B$. $[Co(en)_3]Cl_3$	$Q$. $3$
$C$. $[Pt(NH_3)_2Cl_2]$	$R$. $4$
$D$. $[Pt(NH_3)_3Cl_3]^+$	$S$. $5$

Match the compounds with their total number of stereoisomers and select the correct code:

$A$ metal complex with a formula $MCl_4 \cdot 3NH_3$ is involved in $sp^3d^2$ hybridisation. It upon reaction with excess of $AgNO_3$ solution gives '$x$' moles of $AgCl$. Consider '$x$' is equal to the number of lone pairs of electron present in the central atom of $BrF_5$. Then the number of geometrical isomers exhibited by the complex is $............$

Which of the following complexes of $Co^{3+}$ shows more than one type of isomerism?

Which of the following complex compound$(s)$ is/are paramagnetic and low spin?
$(I) \, K_3[Fe(CN)_6] \quad (II) \, [Ni(CO)_4] \quad (III) \, [Cr(NH_3)_6]^{3+} \quad (IV) \, [Mn(CN)_6]^{4-}$
Choose the correct code:

The $d-$electron configurations of $Cr^{2+}, Mn^{2+}, Fe^{2+}$ and $Co^{2+}$ are $d^4, d^5, d^6$ and $d^7$ respectively. Which one of the following will exhibit minimum paramagnetic behaviour?
(At. nos. $Cr = 24, Mn = 25, Fe = 26, Co = 27$)