Determine whether the series is convergent or divergent. Show your work. List the series test. \text { a. } \sum_{n=1}^{\infty} \frac{\left(1+\frac{\pi}{n}\right)^{3}}{e^{n}} \text { b. } \sum_{n=0}^{\infty} \frac{\pi^{4 n}}{(2 n) !}