2.
[tex]\frac{3}{5}(\frac{5}{3})=\frac{3\times5}{5\times3}=\frac{15}{15}=1[/tex]4.
[tex]\frac{1.3\times8.2}{1.3}=8.2[/tex]6.
[tex]-\frac{3}{5}(-\frac{8}{21})(-\frac{5}{3})=-\frac{8}{21}[/tex]8.
[tex]\frac{-2.4\times\frac{4}{7}}{\frac{4}{7}}=-2.4[/tex]