science

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Across
  1. 4. a natural agent that stimulates sight
  2. 6. to send out signal
  3. 8. to use a code to convert symbols into letters
Down
  1. 1. when light shines on a object
  2. 2. to convert information into on and on or off
  3. 3. to give off light
  4. 5. to use a code convince letters into symbols
  5. 7. a system that signals or symbols to communicate to others