$\frac{a}{x}\times\frac{b}{y}\times\frac{c}{z}$
If a,b,c are rational numbers and x,y,z are natural numbers, then select an option which is true for the given expression.
 

Verify the following:

$\frac{7}{2}\times \frac{3}{5}=\frac{3}{5}\times \frac{7}{2}$

Verify the following:

$\frac{3}{5}+\frac{5}{7}=\frac{5}{7}+\frac{3}{5}$

If $a=\frac{1}{5}$, $b=\frac{1}{3}$ and $c=\frac{-2}{5}$, then verify that $\left(a\times b\right)\times c=a\times (b\times c)$.

Write the reciprocal of $0$.

Verify that $–\left(–x\right)=x$ for $x=\frac{11}{15}$
 

Verify the following: 

$\left(\frac{2}{3}+\frac{4}{5}\right)$ is a rational number