Puzzle 25

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Across
  1. 3. To perceive sounds through the ear.
  2. 4. A piece of knowledge that is hidden and intended to be kept hidden.
  3. 7. A young male.
  4. 8. A joke.
  5. 9. Something added.
Down
  1. 1. A common, round fruit.
  2. 2. The time at which something happens.
  3. 3. To heat.
  4. 5. To become something different.
  5. 6. An amount obtained by the addition of smaller amounts.