crossword of the week (hard)

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Across
  1. 5. not the simplest word
  2. 7. a tool used for writing in the 1800s
  3. 8. a high iq in an idea or a person or animal
Down
  1. 1. a physical object being fired
  2. 2. nothing
  3. 3. a tool used for writing and working in schools nowadays
  4. 4. a room in a school
  5. 6. what is this called