Ответ:

а) \(\frac{3}{4}\cdot8-\left(\frac{2}{3}+\frac{1}{3}\right)\cdot2=6-1\cdot2=4\).

б) \(\left(\frac{5}{6}+\frac{1}{6}\right):\left(\frac{2}{3}-\frac{1}{3}\right)-2=1:\frac{1}{3}-2=3-2=1\).

в) \(\left(\left(\frac{4}{5}-\frac{1}{5}\right)\cdot5+1\right):4=\left(\frac{3}{5}\cdot5+1\right):4=4:4=1\).

г) \(\left(\frac{1}{2}+\frac{1}{3}\right)\cdot\left(1-\frac{1}{5}\right):2=\frac{5}{6}\cdot\frac{4}{5}:2=\frac{2}{3}:2=\frac{1}{3}\).

Ответ: а) 4; б) 1; в) 1; г) \(\frac{1}{3}\).