For each function $f(n)$ below, give an asymptotic upper bound using "big$-$Oh$"$ notation. You should give the tightest bound possible.

$f(n)=nlogn+\frac{n}{5}$

$f(n)=100n^3-7n^3+14n^2$

$f(n)=\mathrm{.}001n^3+100*2^n$

$f(n)=nlogn+n^2$