The Four Color Rule

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Across
  1. 5. Image containing various regions
  2. 6. Separates different regions.
  3. 7. A nation with its own government
  4. 9. Africa, Asia, Europe, North & South America, Antartica, Australia
Down
  1. 1. Where we go to school, ________ University
  2. 2. Red, blue, green, yellow, purple, pink, orange...
  3. 3. Minimum number needed to color in any 2D map.
  4. 4. A portion of a map
  5. 8. ___-Dimensional, flat w/ no depth.