Find the area of inscribed convex octagon, if the length of four sides is $2$, and length of other four sides is $ 6\sqrt {2}$.

$\textbf{(A)}\ 120 \qquad\textbf{(B)}\  24 \plus{} 68\sqrt {2} \qquad\textbf{(C)}\  88\sqrt {2} \qquad\textbf{(D)}\ 124 \qquad\textbf{(E)}\  72\sqrt {3}$