The picture top left shows a person looking through the damaged section where the aircraft had entered the building and top right shows a young woman trying to get help. 

Question:

If the temperature here was hot enough to melt steel (Steel melts at 1539 degrees. Jet fuel (kerosine) burns at 825 degrees under ideal conditions) then how come it was cool enough to allow these unfortunate people to survive there? You will of course notice that there is no sign whatsoever of any fire or smoke here.