8. Which of the following 3 series is/are convergent?__ (8)__

(a) $$\sum{n=1}^{\infty} e^{-n} n!$$ (b) $$\sum{n=1}^{\infty} \left(\frac{-2n}{n+2}\right)^{2n}$$ (c) $$\sum_{n=1}^{\infty} \frac{\sin n}{3^n}$$