The total number of possible isomers for the complex compound $[Cu^{II}(NH_3)_4][Pt^{II}Cl_4]$ are

If the spin-only magnetic moment of $VCl_x$ is $1.73 \ BM$,then the correct formula is:

Amongst the following ions,which one has the highest magnetic moment value?
$(i)$ $[Cr(H_2O)_6]^{3+}$
$(ii)$ $[Fe(H_2O)_6]^{2+}$
$(iii)$ $[Zn(H_2O)_6]^{2+}$

The diamagnetic species is

Total number of unpaired electrons present in the central metal atoms/ions of $[Ni(CO)_{4}]$, $[NiCl_{4}]^{2-}$, $[PtCl_{2}(NH_{3})_{2}]$, $[Ni(CN)_{4}]^{2-}$ and $[Pt(CN)_{4}]^{2-}$ is . . . . . . .

The type of isomerism between $[Co(en)_2(NCS)_2]Cl$ and $[Co(en)_2(NCS)Cl]NCS$ is ............ .