1. उत्तल   heptagon   perpendicular lines   pentagon   convex   Hint Half-n-half Clue   2. समानांतर रेखाएँ   hemisphere   quadrangle   parallel lines   hexagon   Half-n-half Clue   3. लंब रेखाएँ   parallelogram   plane   perpendicular lines   edge   Half-n-half Clue   4. समानांतर चतुर्भुज   ellipse   parallelogram   polygon   vertex   Half-n-half Clue   5. किरण   ellipse   plane   straight line   ray   Half-n-half Clue   6. किनारा   pyramid   vertex   hemisphere   edge   Half-n-half Clue   7. समचतुर्भुज   rhombus   perpendicular lines   parallelogram   quadrilateral   Half-n-half Clue