
| • | Face A has 1 contour and 4 edges. |
| • | Edge E2 is the intersection of faces A and B. |
| • | Edge E2 is a component of contours C1 and C2. |

| • | Face A has 1 contour and 6 edges. |
| • | Face B has 2 contours and 8 edges. |
| • | Face C has 1 contour and 4 edges. |

| • | Face A has 1 contour and 6 edges. |
| • | Face B has 1 contour and 4 edges. |
| • | Face C has 1 contour and 4 edges. |
| • | Face D has 1 contour and 4 edges. |