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The region of convergence of $Z$-transform of the sequence
$\left(\frac{5}{6}\right)^{n} u(n)-\left(\frac{6}{5}\right)^{n} u(-n-1)$ must be

1. $|z|<\frac{5}{6}$
2. $|z|>\frac{6}{5}$
3. $\frac{5}{6}<|z|<\frac{6}{5}$
4. $\frac{6}{5}<|z|<\infty$