Problem $1$: Design an NFA for each language below $($alphabet $\backslash$Sigma $=\{$a$,$ b$\}$ unless otherwise stated, note: some problems state how many states your NFA should have$).$

$1.$ The language of all strings from $\backslash$Sigma $*$ ending with bb $/$ NFA with three states.

$2.$ L$($ aa$*($a $+$ b$))$

$2.$ L$($a$*$b$*$a$*$a$)/$ NFA with three states.

$3.$ All string from $\backslash$Sigma $*$ that contain substring bb or contain even number of b$$s$\}(\backslash$Sigma $=\{$a$,$ b$,$ c$\})4.$ All strings from $\backslash$Sigma $*$ that contain substring ab exactly once