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1. What is the highest mountain in the world?
2. Where is the Grand Canyon?
3. How much rain does the Atacama desert receive per year?
4. How long is the Nile River?
5. How old is Mt.Everest?
6. Which is taller, Victorial or Niagara Falls?
7. When was Thien Duong Cave discovered?
8. How can visitors get to Angel Fails?