Across
- 3. The scientist who specialize in study of oceans are called.
- 5. Some of the rain water get collected underground on the bed ok rock.
- 6. The longest river in the world is.
- 7. What we mix with hydrogen to make water.
Down
- 1. When solid is changing into gas it called.
- 2. Ensures the flow of fresh water on land.
- 4. Full form of RO is.