Across
- 4. covers 71% of the earth
- 5. produces oxygen, to help breath
- 6. the biggest and coldest desert
- 8. great plains, these plains began over a billion years ago
- 9. the world's most populated island with over 130 million people
Down
- 1. formed by tectonic plates
- 2. a landform that is situated between mountains
- 3. the study of the word
- 7. forests, 10,000 millimeters of water per year