$(I)\, Pt(SCN)_2 - 3PEt_3,$ $(II)\,CoBr ·SO_4 · 5NH_3$ $(III)\, FeCl_2 · 6H_2O$
$(II) \,[CoBr(NH_3)_5]SO_4:$ Exhibit only ionization isomerism.
$(III)\, [Fe(H_2O)_6]Cl_2:$ Exhibits only hydrate isomerism.
$(a)$ $\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{3} \mathrm{Cl}\right]^{+}$
$(b)$ $\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right) \mathrm{Cl}_{5}\right]^{-}$
$(c)$ $\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{2} \mathrm{Cl}\left(\mathrm{NO}_{2}\right)\right]$
$(d)$ $\left[\mathrm{Pt}\left(\mathrm{NH}_{3}\right)_{4} \mathrm{ClBr}\right]^{2+}$
($en=$ ઇથિલીન ડાય એમાઈન)