A cube is made by soldering twelve 3-inch lengths of wire properly at the vertices of the cube. If a fly alights at one of the vertices and then walks along the edges, the greatest distance it could travel before coming to any vertex a second time, without retracing any distance, is:
<spanclass=′latex−bold′>(A)</span> 24 in.<spanclass=′latex−bold′>(B)</span> 12 in.<spanclass=′latex−bold′>(C)</span> 30 in.<spanclass=′latex−bold′>(D)</span> 18 in.<spanclass=′latex−bold′>(E)</span> 36 in. geometry3D geometrytopology