\[\boxed{\mathbf{77}\mathbf{.}}\]
\[1)\ \left( a^{4} \right)^{- \frac{3}{4}} \bullet \left( b^{- \frac{2}{3}} \right)^{- 6} =\]
\[= a^{- 3} \bullet b^{\frac{12}{3}} = a^{- 3} \bullet b^{4} = \frac{b^{4}}{a^{3}}\]
\[2)\ \left( \left( \frac{a^{6}}{b^{- 3}} \right)^{4} \right)^{\frac{1}{12}} = \left( a^{6} \bullet b^{3} \right)^{\frac{4}{12}} =\]
\[= a^{\frac{24}{12}} \bullet b^{\frac{12}{12}} = a^{2}b\]