The speed of nitrogen molecules in the atmosphere (at 20ºC) follows a normal distribution with a mean speed of 500 meters/second and a standard deviation of 50 meters/second. Which conclusion does this information best support?


84% of the molecules have speeds between 450 meters/second and 550 meters/second.


68% of the molecules have speeds between 450 meters/second and 550 meters/second.


50% of the molecules have speeds between 450 meters/second and 550 meters/second.


34% of the molecules have speeds greater than 550 meters/second.