since you don't know what GOOGLE is... type WWW.GOOGLE.com and search for "POPULAR MECHANICS" and "twin towers" and all your little LIHOP/MIHOP foolishness goes right down the drain. they explain it all.I will save him the time and directly link it.
http://www.popularmechanics.com/science/defense/1227842.html?page=5&c=y