How many significant figures in the following numbers?
  1. 3423.34=6
  2. 2304.3=5
  3. 2050=3
  4. .0342=3
  5. 3434.34340= 9
  6. 4=1
  7. 400=1
  8. .4=1
  9. .40=2
  10. .400=3
  11. 10000000000=1
  12. 1=1
  13. 1.00=3
  14. 304050607=9
  15. 99=2
  16. number of doors in this room=2
  17. number of glass cabinets in this room=22
  18. number of drawers in this room=32
  19. number of chairs and stools in this room=32
  20. number of people cooler than Mr. Bair (hint the answer is zero, but not according to his wife =)) a million people are cooler then mr. bair