Answer:
[tex]{ \tt{ (\frac{ {5}^{ - 4} }{ {4}^{ - 6} } ) \times {5}^{3} }} \\ \\ = { \tt{ \frac{ {5}^{ - 4} . {5}^{3} }{ {4}^{ - 6} } }} \\ \\ { \tt{ = \frac{ {5}^{ - 1} }{ {4}^{ - 6} } }} \\ { \tt{ = \frac{ {4}^{6} }{ {5}^{1} } }} \\ = { \tt{ \frac{4096}{5} }} \\ \\ = 819.2[/tex]