Why did the British handover Hong Kong?

Related questions

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4. Is Hong Kong a country Yes or no?
5. Can Britain take back Hong Kong?
6. What is the oldest religion text?
7. What is the capital of Hong Kong?
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Tags

1. #choice
2. #nanking
3. #territories
4. #china
5. #ships
6. #pledged
7. #little
8. #opium
9. #first
10. #ceded
11. #might
12. #perpetuity
13. #treaty
14. #british
15. #their
16. #given
17. #meant
18. #military