Across
- 5. A polygon with three sides. (8 letters)
- 7. A tool used to measure weight. (5 letters)
- 9. Heart The organ responsible for pumping blood. (5 letters)
- 11. A period of ten years. (5 letters)
- 12. The planet known as the "Red Planet." (4 letters)
- 13. The main source of energy for Earth. (3 letters)
- 14. The gas we breathe in to survive. (6 letters)
- 15. The layer of air around Earth. (9 letters)
- 16. The study of living organisms. (7 letters)
- 17. Nairobi The capital city of Kenya. (7 letters)
- 19. The smallest continent by area. (9 letters)
Down
- 1. The green pigment in plants. (11 letters)
- 2. The hardest natural substance. (7 letters)
- 3. The freezing point of water in Celsius. (5 letters)
- 4. A shape with four equal sides and angles. (6 letters)
- 6. A famous physicist who developed the theory of relativity. (8 letters)
- 8. The fourth planet from the Sun. (4 letters)
- 10. The branch of science dealing with stars and planets. (10 letters)
- 16. The study of numbers and shapes. (11 letters)
- 18. The chemical symbol for water. (2 letters)