Distributing the exponent:
[tex]\begin{gathered} 3^{10}\lbrack(32^5)^2\cdot3^2\rbrack= \\ =3^{10}(32^{5\cdot2}\cdot3^2)= \\ =3^{10}(32^{10}\cdot3^2) \end{gathered}[/tex]Applying commutative property:
[tex]\begin{gathered} 3^{10}\cdot3^2\cdot32^{10}= \\ =3^{10+2}\cdot32^{10}= \\ =3^{12}\cdot32^{10} \end{gathered}[/tex]