Tính

Bài 1: Tính

$$\begin{gathered} \mathrm{a}) \frac{3}{5}+\left(\frac{-4}{3}\right)+\left(\frac{-3}{4}\right) \\ \mathrm{b}) \frac{5}{8} - \left(\frac{-2}{5}\right) - \frac{3}{10} \\ \mathrm{c}) \left(\frac{-7}{2}\right) + \left(\frac{-2}{3}\right) + \left(\frac{-3}{5}\right) \\ \mathrm{d}) \frac{3}{4}- \left[\left(\frac{-5}{3}\right) - \left(\frac{1}{12}+\frac{2}{9}\right)\right] \end{gathered}$$