Write empirical formula

Answer:
[tex]Pb_{3}(PO_{4})_{4}\\Pb(IO_{3})_{4}\\\\FePO_{4}\\\Fe(IO_{3})_{3}[/tex]
Explanation:
[tex]Pb^{4+}_{3}(PO_{4}^{3-})_{4}---> Pb_{3}(PO_{4})_{4}\\Pb^{4+}(IO_{3}^{-})_{4}--->Pb(IO_{3})_{4}\\\\Fe^{3+}PO_{4}^{3-}---> FePO_{4}\\\Fe^{3+}(IO_{3}^{-})_{3}--->Fe(IO_{3})_{3}[/tex]