What do the first 3 digits of a ZIP code mean?

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Tags

1. #first
2. #facility
3. #united
4. #processing
5. #divides
6. #large
7. #digits
8. #conjunction
9. #numbered
10. #sectional
11. #groups
12. #digit
13. #northeast
14. #these
15. #center
16. #states
17. #represent