(i)
\(\frac{-3}{5}\times\frac{10}{7}\)
\(=\frac{-3\times10}{5\times7}\)
\(=\frac{-30}{35}=\frac{-30\div5}{35\div5}=\frac{-6}{7}\)
(ii)
\((\frac{-5}{8})^{-1}\)
\(=\frac{8}{-5}=\frac{8\times-1}{-5\times-1}=\frac{-8}{5}\)
(iii)
\((-6)^{-1}\)
\(=\frac{1}{-6}=\frac{1\times-1}{-6\times-1}=\frac{-1}{6}\)