human
What are some interesting facts about the world?
assistant
1. The Earth is approximately 4.5 billion years old.
2. There are over 7000 languages spoken in the world today.
3. The Great Wall of China is the longest man-made structure in the world, measuring an impressive 8,851 km long.
4. The human brain has a volume of 1.2 liters and consumes 20% of our energy intake.
5. The average life expectancy at birth is 71.8 years for men and 76.9 years for women.