Challenge it Crossword Puzzle

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Across
  1. 4. The distance from one crest to the next one
  2. 8. When the particles are spread out
  3. 9. Highest point on a wave
Down
  1. 1. Wave: A wave that displaces matter in the direction its traveling
  2. 2. When the particles are close together
  3. 3. Distance from rest point to crest or trough
  4. 4. a disturbance that transfers energy
  5. 5. Lowest points on a wave
  6. 6. wave: A wave that moves perpendicular to the direction of the wave
  7. 7. a material that a wave travels through