I was going off of freefall times that someone else came up with. According to this video, freefall for flat steel beams would be 5.6 seconds over the distance of 100 meters.
http://youtube.com/watch?v=Ml_n5gJgQ_U
So we divide 100 meters into the height of WTC 2 (415m) We get 4.15.
4.15 X 5.6 = 23.24 seconds.

Remind readers again of your credentials with regard to structural engineering. Many thanks!
Yeah, but the only alt-XXXX I know is alt-0232 because of my friend Michèle, so I used that one.
In most Windows apps, hitting Ctrl-' and then e will give you the accented e character, but it seems not to work in Firefox.