1. quadrilátero   pentagon   hemisphere   quadrilateral   straight line   Hint Half-n-half Clue   2. raio   concave   ray   pentagon   quadrangle   Half-n-half Clue   3. convexo   hexagon   convex   straight line   vertex   Half-n-half Clue   4. quadrilátero   prism   plane   concave   quadrangle   Half-n-half Clue   5. retas paralelas   plane   parallel lines   ellipse   perpendicular lines   Half-n-half Clue   6. prisma   pyramid   segment   ellipse   prism   Half-n-half Clue   7. losango, rombo   plane   parallel lines   rhombus   ellipse   Half-n-half Clue