Thực hiện phép tính ( tính hợp lí nếu có thể)

$\begin{array}{l}a)\frac{1}{15}+\frac{2}{3}+\frac{-3}{5}\\ \\ b)\frac{-1}{2}+\frac{2}{5}-\frac{3}{10}\\ \\ c)\frac{1}{4}+\frac{-9}{11}+\frac{7}{4}+\frac{-2}{11}\\ \\ d)\frac{-9}{8}+\frac{4}{7}+\frac{1}{8}+\frac{10}{7}\\ \\ e)\frac{-6}{11}+\left(\frac{-2}{3}+\frac{-5}{11}\right)\\ \\ f)\frac{5}{15}+\frac{-11}{4}-\left(\frac{1}{3}-\frac{11}{4}\right)\\ \\ g)\left(9\frac{2}{9}+\frac{3}{5}\right)-7\frac{2}{9}\\ \\ h)\left(\frac{55}{6}-2\frac{4}{7}\right)-\left(5\frac{1}{6}+\frac{3}{7}\right)\end{array}$