\(1+1^{1098}=1+1=2\)

\(\dfrac{7}{3}+\left[\left(-\dfrac{5}{6}\right)+\left(-\dfrac{2}{3}\right)\right]=\dfrac{7}{3}-\dfrac{5}{6}-\dfrac{2}{3}=\dfrac{5}{3}-\dfrac{5}{6}=\dfrac{5}{6}\)

\(\left[\left(-0,25\right)-\dfrac{3}{4}\right]:\left(-5\right)-3.\left(-\dfrac{1}{2}\right)^2+\dfrac{1}{5}\\ =\left[-\dfrac{1}{4}-\dfrac{3}{4}\right]:\left(-5\right)-3.\dfrac{1}{4}+\dfrac{1}{5}\\ =\left(-1\right):\left(-5\right)-\dfrac{3}{4}+\dfrac{1}{5}\\ =\dfrac{1}{5}-\dfrac{3}{4}+\dfrac{1}{5}\\ =-\dfrac{7}{20}\)