Simplify. Express your answer using positive exponents. \( \left(5 z^{7}\right)\left(8 z^{-1}\right)\left(6 z^{3}\right) \) \begin{tabular}{l} Submit \\ \( \square \square \square \) \\ \hline\end{tabular}

To simplify \( \left(5 z^{7}\right)\left(8 z^{-1}\right)\left(6 z^{3}\right) \), we start by multiplying the coefficients together: \(5 \times 8 \times 6 = 240\). Next, we combine the \(z\) terms by adding the exponents: \[ z^{7} \times z^{-1} \times z^{3} = z^{7 + (-1) + 3} = z^{9}. \] Putting it all together, we have \[ 240 z^{9}. \] So, the simplified expression is: \(\boxed{240 z^{9}}\)