Science crossword puzzle

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Across
  1. 1. Projected by the sun, rhymes with day.
  2. 4. The absence of brightness.
  3. 7. The absence of darkness.
  4. 8. You can see right through me.
  5. 9. Originates from
Down
  1. 1. Changes direction of light
  2. 2. The purpose of a mirror.
  3. 3. I can be any colour that you can't see through.
  4. 5. I am present in the light and absent in the dark.
  5. 6. I am neither opaque nor transparent.