Verified answer

7)

[tex]{m}^{3} [/tex]

8)

[tex]8 {a}^{3} {b}^{3} [/tex]

9)

[tex]4 {m}^{2} {n}^{2} [/tex]

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Успехов!)

[tex]\displaystyle\bf\\1)\\\\m^{9} \cdot \boxed{m^{3}} =m^{12} \\\\\\2)\\\\\Big(2ab\Big)^{3} =2^{3} \cdot a^{3} \cdot b^{3} =\boxed{8a^{3} b^{3} }\\\\\\3)\\\\\Big(-2mn\Big)^{2} =\Big(-2\Big)^{2} \cdot m^{2} \cdot n^{2}=\boxed{4m^{2} n^{2} }[/tex]