Crossword Puzzle

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Across
  1. 1. To find the total.
  2. 5. Period of 1000 years.
  3. 6. A line segment connecting the center of a circle to any point on its circumference.
  4. 8. A three-sided polygon.
Down
  1. 2. Collection of 12 items.
  2. 3. Period of 100 years.
  3. 4. The result of addition.
  4. 7. The shape of a ball.
  5. 8. No.that makes a pair.