Write empirical formula

Answer:
[tex]Fe(MnO_{4})_{2}\\\\ Fe(IO_{3})_{2}\\\\NH_{4}MnO_{4}\\\\NH_{4}IO_{3}[/tex]
Explanation:
[tex]Fe^{2+}(MnO_{4}^{-})_{2}--->Fe(MnO_{4})_{2}\\\\Fe^{2+}(IO_{3}^{-})_{2}---> Fe(IO_{3})_{2}\\\\NH_{4}^{+}MnO_{4}^{-}--->NH_{4}MnO_{4}\\\\NH_{4}^{+}IO_{3}^{-}--->NH_{4}IO_{3}[/tex]