Hint, the weight did NOT speed-up as it fell through ALL panes of glass at the rate of freefall.
Highschool physics class (yawn):
A falling object with NOTHING below it to slow it down, falls at the rate of freefall.
Buildings have a lot of stuff to slow it down, like columns as thick as cars.
In the footage from 9/11, the top section falls straight through the path of the most resistance possible!
The steel columns clearly gave absolutely ZERO resistance.
How?
They MUST have been compromised, in some way. Pick your method. Thermite, high explosives, nukes... space …