CROSWORD 7PLUS

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Across
  1. 1. produced from refrigeration equipment
  2. 4. a gas that can cause global warming from manure
  3. 8. the covering of the water surface by algae
  4. 9. of mosquitoes and lizards
  5. 10. cutting down forests
  6. 11. substances that cause pollution
  7. 12. relationship between bean roots and Rhizobium bacteria
Down
  1. 2. between cattle and goats on pasture
  2. 3. between sharks and remora
  3. 5. chemical element with the symbol Pb
  4. 6. between host plant and orchid
  5. 7. between lice and head hairs
  6. 10. synthetic insecticide