\(A=\left(\frac{1999}{2011}-\frac{2011}{1999}\right)-\left(\frac{-12}{1999}-\frac{12}{2011}\right)\) \(D=\frac{-7}{318}+496.\left(\frac{-7}{813}\right)+\left(\frac{-7}{813}\right).316\)
\(B=\frac{2}{5}\left(\frac{3}{11}+\frac{-2}{5}\right)\)
\(C=\frac{-5}{7}.\frac{4}{13}+\frac{-5}{7}.\frac{9}{13}+\frac{-2}{7}\) \(E=\frac{-9}{10}.\frac{5}{14}+\frac{1}{10}.\left(\frac{-9}{2}\right)+\frac{1}{7}.\left(\frac{-9}{10}\right)\)