Pi Day Madness

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Across
  1. 1. all of the numbers following 3 in pi are--
  2. 3. the area of a circle is Pi*--
  3. 4. --are used to approximate Pi.
  4. 10. Pi*radius squared is the area of a--
  5. 12. computers -- pi as a form of a stress test.
  6. 14. Pi has played a major role in what subject?
  7. 17. “ -- the circle”is to measure the diameter of a circle by building a square inside the circle.
  8. 19. Pi contains over a million--
  9. 20. Pi Day is in what month?
Down
  1. 2. Pi's cotangent is--
  2. 5. 4*Pi*radius squared is a sphere's--
  3. 6. Pi*diameter equals--
  4. 7. 4 divided by 3*Pi radius cubed is a sphere's--
  5. 8. Pi is an -- number.
  6. 9. the symbol of pi came from the -- alphabet.
  7. 11. 3.14159... is approximately--
  8. 13. Albert-- was born on 03.14.1879
  9. 15. Pi rounded is equal to--
  10. 16. Pi is also referred to as the “ -- constant.”
  11. 18. the Greek letter π is called--