Across
- 2. Essential gas for human respiration
- 4. System of government by the people
- 8. Process of gradual change over time
- 13. French military and political leader
- 14. Study of the mind and behavior
- 16. Global computer network connecting millions of devices
- 17. Earth's natural satellite
- 18. Famous playwright and poet
Down
- 1. Period of cultural and artistic rebirth in Europe
- 3. Third planet from the Sun
- 5. Influential classical composer
- 6. Genetic material that carries hereditary information
- 7. Force that attracts objects toward each other
- 9. Mountain that erupts with lava and ash
- 10. Process by which plants convert sunlight into energy
- 11. Physicist known for the theory of relativity
- 12. Sculpture representing a person or object
- 15. System Sun and all the celestial objects orbiting around it