Tính:
a)\([\left(-\frac{1}{2}\right)^3-\left(\frac{3}{4}\right)^3\cdot\left(-2\right)^2]:[2\cdot\left(-1\right)^5+\left(\frac{3}{4}\right)^2-\frac{3}{8}\)
b)\([\left(\frac{4}{3}\right)^{-2}\left(\frac{3}{4}\right)^4]:\left(\frac{3}{2}\right)^6\)
help me!!!!!!!!!!!!!!