급수 $\displaystyle \sum _ {n=1} ^ {\infty} {\frac{(-1) ^n} {n} \frac{(5x-1) ^n} {3^n}}$ 의 수렴구간은?

• ①$\displaystyle \left [- \frac{2} {3}, \frac{4} {3} \right)$
• ②$\displaystyle \left (- \frac{2} {3}, \frac{4} {3} \right]$
• ③$\displaystyle \left [- \frac{2} {5}, \frac{4} {5} \right)$
• ④$\displaystyle \left (- \frac{2} {5}, \frac{4} {5} \right]$
• ⑤$\displaystyle \left [- \frac{2} {7}, \frac{4} {7} \right)$