$a-\frac{4^n}{1+9^n}$

$b-\frac{(-1{)}^{n+1}.n}{n+\sqrt[\phantom{2}]{n}}$

$c-\frac{cos(n)}{2^n}$

$d-n^{\frac{1}{n}}$

$e-n.sin(\frac{1}{n})$

$f-n-\sqrt[\phantom{2}]{n^2+4n+3}$

$g-\frac{(-3{)}^n}{n!}$

$h-\frac{(-1{)}^n}{2\sqrt[\phantom{2}]{n}}$

Determine if they are convergent or divergent.