What’s in a number?

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Across
  1. 4. not used up (para 5)
  2. 5. guess (para 3)
  3. 6. gadget for playing video games (para 5)
  4. 8. imagine (para 3)
Down
  1. 1. of the usual size or shape (para 3)
  2. 2. continuing to live (para 1)
  3. 3. make a connection in your mind (intro)
  4. 7. say something clearly and exactly (para 1)