Across
- 4. Three percent of the water on Earth is _____ water
- 5. all water on the Earth
- 8. water is transparent to this which allows plants to live under water
- 9. Water's fitness of a particular use is known as
- 11. sewer systems can contaminate water, and carry away
- 12. herbicides kill weeds and add ______ to plants and animals
Down
- 1. this means careful use
- 2. what type of resources cannot be made by humans
- 3. fertilizers increase plant
- 6. affect water quality by polluting or conserving water
- 7. these type of roads improve surface tension
- 10. this type of irrigation uses lots of water