List 3 word work

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Across
  1. 2. to put a stamp on after its mailed
  2. 5. an automatic vehicle
  3. 6. someone the studies space
  4. 7. a signature
  5. 9. a group of 3 movies, book etc.
Down
  1. 1. the study of space
  2. 3. a person that goes up into space
  3. 4. a book by the person its about
  4. 8. a 3 wheeled vehicle
  5. 9. people that make videos professionally use it