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Across
  1. 3. Happening suddenly or by a large amount
  2. 5. To go down or become smaller in number
  3. 7. To reach the highest point
  4. 9. To reach the lowest point
  5. 10. To change frequently between higher and lower levels
Down
  1. 1. To compare two things by showing how they are different
  2. 2. To go up or become greater in number
  3. 4. To stay at the same level
  4. 6. A very large or noticeable change
  5. 8. Happening slowly over a period of time