[178]Prerequisites:[0Q8],[174].Given \(A⊂ ℝ^ n\) convex with non-empty interior, show that \(\overline A= \overline{({{A}^\circ })}\) (the closure of the interior of \(A\)). Then find a simple example of \(A\) for which \(\overline A≠ \overline{({{A}^\circ })}\).