Tính
a)\(\frac{\left(\frac{3}{4}\right)^2-\left(-\frac{4}{5}\right)^2.\left(-1\right)^7}{\left(\frac{2}{3}\right)^3.\left(-\frac{5}{2}\right)^3}\)
b) \(\frac{16^{13}.3^{10}+120.6^9}{4^6.3^{12}+6^{11}}\)
c) \(\frac{1}{3}-\frac{1}{18}-\frac{1}{54}-\frac{1}{108}-\frac{1}{180}-\frac{1}{270}-\frac{1}{378}\)
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