Thực hiện phép tính: (2 điểm)
a) $1-\dfrac{1}{2}+\dfrac{1}{3}$ ;
b) $\dfrac{2}{5}+\dfrac{3}{5}: \dfrac{9}{10}$ ;
c) $\dfrac{7}{11} \cdot \dfrac{3}{4}+\dfrac{7}{11} \cdot \dfrac{1}{4}+\dfrac{4}{11}$ ;
d) $\left(\dfrac{3}{4}+0,5+25 \%\right) \cdot 2 \dfrac{2}{3}$ .