Across
- 4. a form of writing used in ancient Mesopotamia
- 6. the plain between two rivers
- 8. the middle period of Stone Age
- 10. the height above sea level
Down
- 1. a group of people moving from place to place
- 2. of the moon or related to moon
- 3. a factory where petroleum is refined
- 5. sowing season beginning at the start of monsoons
- 7. a solid, naturally occurring inorganic substance
- 9. crops cultivated for extracting oil