Which of the following compounds will exhibit coordination isomerism?

Which of the following will show optical isomerism?
$I$. $\text{Cis}-[Co(NH_3)_2(en)_2]^{3+}$
$II$. $\text{Trans}-[IrCl_2(C_2O_4)_2]^{3-}$
$III$. $[Rh(en)_3]^{3+}$
$IV$. $\text{Cis}-[Ir(H_2O)_3Cl_3]$

Select the incorrect match.

The magnetic moment is measured in Bohr Magneton $(BM)$. Spin only magnetic moment of $Fe$ in $[Fe(H_2O)_6]^{3+}$ and $[Fe(CN)_6]^{3-}$ complexes respectively is:

The compounds $[Cr(H_2O)_6]Cl_3$,$[Cr(H_2O)_5Cl]Cl_2 \cdot H_2O$ and $[Cr(H_2O)_4Cl_2]Cl \cdot 2H_2O$ exhibit:

$STATEMENT-1$: The geometrical isomers of the complex $[M(NH_3)_4Cl_2]$ are optically inactive.
$STATEMENT-2$: Both geometrical isomers of the complex $[M(NH_3)_4Cl_2]$ possess a plane of symmetry.