3: [tex]\frac{\sqrt[12]{972}}{2}[/tex]
5: [tex]-\frac{1}{64}[/tex]
6: [tex]\frac{1}{27}[/tex]
7: [tex]\frac{a^3}{4b^4c^3}[/tex]
8: [tex]\frac{16m^6n^14p^4}{9}[/tex]
9: 672 = 4[tex]\sqrt{42}[/tex]