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Related Clues:
- Extensive periods
- The Hadean, the Archean and the Proterozoic, e.g
- **Ages and ages (2 and 3)
- Earth's longest time divisions, geologically
- Astronomical time periods
- Periods of quiet — manage to get upset
- Extremely long times
- Very long stretches of time
- One's embarrassed for ages
- Geologic time frames
- Very long time spans
- The Times: can it manage reverses?
- Dating periods for geologists?
- Geologic spans
- Extreme stretches