Assuming  $100\%$  ionization of the following in aqueous solutions, 
(i)  $\left[\text{Pt}{\left({\text{NH}}_3\right)}_6\right]{\text{Cl}}_4$   (ii) $\left[\text{Cr}{\left({\text{NH}}_3\right)}_6\right]{\text{Cl}}_3$    (iii) $\left[\text{Co}{\left({\text{H}}_2\text{O}\right)}_5\text{Cl}\right]{\text{Cl}}_2$   (iv) NaCl
The increasing order of conductivity is