Find the code

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Across
  1. 2. Highest mountain above sea level
  2. 3. Days in a week
  3. 6. Shape with three sides
  4. 9. Gas that humans need to breathe
  5. 10. Planet famous for its rings
  6. 11. Legs on a spider
  7. 13. Australian animal that carries its young in a pouch
  8. 14. Largest planet in our Solar System
  9. 15. Number system that uses only 0 and 1
Down
  1. 1. Process plants use to make food using sunlight
  2. 4. Closest planet to the Sun
  3. 5. Landform that erupts with lava
  4. 7. Seasons in a year
  5. 8. Australian marsupial that spends most of its life in eucalyptus trees
  6. 12. Largest ocean on Earth