Simplify and express in the form a+bi

\((3+4i)+ (8+3i)\)

\begin{align} 3+8+4i+3i\\ = 11 +7i\end{align}

\((2+7i)-(4+i)\)

\begin{align} 2-4+7i-i\\ = -2 +6i\end{align}

\((-1-5i)-(3+4i)-2(6-2i)\)

\begin{align} -1-3-12-5i-4i+4i\\ = -16 -5i\end{align}

\( (2 \sqrt{3} +5i)-(3 \sqrt{3}-i)\)

\begin{align}2 \sqrt{3}-3 \sqrt{3}+5i+i\\ = -\sqrt{3}+6i\end{align}