thực hiện các phép tính sau:
A =\(\frac{5.2^{30}.3^{18}-4.3^{20}.2^{27}}{5.2^9.2^{19}.3^{19}-7.2^{29}.3^{18}}\)
B = 1 - 3 + 5 - 7 + 9 - 11 + ..... + 2017 - 2019
C =\(\left(\frac{151515}{606060}+\frac{151515}{121212}+\frac{151515}{202020}+\frac{151515}{303030}+\frac{151515}{424242}\right).\frac{28}{15}\)