Counterexample

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Across
  1. 1. All cars have headlights (4,4)
  2. 3. All animals living in the ocean are fish
  3. 7. Counterexamples are used against this
  4. 8. All prime numbers are odd
  5. 9. All cats have fur (6,3)
  6. 10. All trees lose their leaves in the winter
Down
  1. 2. An example that refutes or disproves a proposition, generalization, or theory.
  2. 4. All states have rectangular state flags
  3. 5. All cars require gas (8,4)
  4. 6. All words in the English language has a vowel