C) \(\frac{7}{2}+\frac{7}{6}+\frac{7}{12}+\frac{7}{20} = \frac{7}{90}\) d) \(A = -7 + 7^2 + 7^3 + ... + 7^{2019}\) e2) \(\frac{15}{12} + \frac{5}{13} + \frac{3}{12} - \frac{18}{13}\)

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c) \(\frac{7}{2}+\frac{7}{6}+\frac{7}{12}+\frac{7}{20} = \frac{7}{90}\)

d) \(A = -7 + 7^2 + 7^3 + ... + 7^{2019}\)

e2) \(\frac{15}{12} + \frac{5}{13} + \frac{3}{12} - \frac{18}{13}\)