1. Blue is everyone's favourite colour.
2. Ancient peoples may not have been able to see the colour blue.
3. In Japan, traffic goes when the light turns "blue."
4. Water only looks blue because it absorbs red, yellow, and orange light waves.
5. All people with blue eyes are distantly related.
6. The colour blue was used for important figures in classic paintings.
7. Blue is used in over half of the world's national flags.
8. Some offices are designed around the colour blue because it can make people more productive.
9. It also has the potential to be an appetite suppressant.
10. Blue is one of the rarest colours you'll see in the natural world.
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