Integers puzzle

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Across
  1. 2. Flying mammal
  2. 4. Negative and positive number including zero
  3. 7. pair opposite number that sum up to zero
  4. 8. Has a trunk
  5. 9. Man's best friend
Down
  1. 1. value distance from number and zero
  2. 3. Likes to chase mice
  3. 5. number fractions written as a fraction
  4. 6. Large marsupial