The cation is sodium ion and the anion is the complex ion. The ligands present are ammine, bromo, chloro, and nitro$-N$. Here $N$ represents that the nitro group coordinates through the $N$ atom. The names of the ligands are written in the alphabetical order. The oxidation state of platinum is $+2$. The oxidation state is written in Roman numerals inside the parenthesis.
$(i)\, [Cr(NO_3)_3 (NH_3)_3]$ $(ii)\, K_3[Co(C_2O_4)_3]$
$(iii)\, K_3[CoCl_2(C_2O_4)_2]$ $(iv)\, [CoBrCl(en)_2]$