Math

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Across
  1. 4. 0,9
  2. 8. starts at 1 ends at ∞
  3. 9. x
  4. 11. 12:15
  5. 12. -
  6. 13. horse shoe method
Down
  1. 1. +
  2. 2. starts at 0 ends at ∞
  3. 3. starts at 1 ends at ∞
  4. 5. starts at 2 ends at ∞
  5. 6. we have it on Friday
  6. 7. M?={...}
  7. 10.