\(a,=\left(\dfrac{3}{5}+\dfrac{3}{5}+\dfrac{6}{5}\right)\times\left(\dfrac{6}{7}:7\right)=3\times\dfrac{6}{49}=\dfrac{18}{49}\)
\(\dfrac{3}{5}\times\dfrac{6}{7}+\dfrac{3}{5}:7+\dfrac{6}{5}\\ =\dfrac{3}{5}\times\dfrac{6}{7}+\dfrac{3}{5}\times\dfrac{1}{7}+\dfrac{6}{5}\\ =\dfrac{3}{5}\times\left(\dfrac{6}{7}+\dfrac{1}{7}\right)+\dfrac{6}{5}\\ =\dfrac{3}{5}+\dfrac{6}{5}=\dfrac{9}{5}\)