The answers to the following clues will have something in common.

1. Fertile Crescent river
2. Father of geometry
3. Muse of music
4. California state motto and city
5. Koala home
6. Intense feeling of joy
7. "Between jobs," for example
8. Countries that share the same national currency
9. Greek dramatist of the Golden Age
10. Controversial area in study of heredity

Answers:

1. Euphrates
2. Euclid
3. Euterpe
4. Eureka
5. Eucalyptus tree
6. Euphoria
7. Euphemism
8. Eurozone
9. Euripides
10. Eugenics 

Credit: Will Shortz
NPR Weekend Edition Sunday Puzzle
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