9/11 Conspiracy theories

Use the following sites to answer the questions:

"The Truth about 9/11 Conspiracy Theories"
http://www.sfgate.com/cgi-bin/article.cgi?file=/gate/archive/2006/04/19/cstillwell.DTL

http://www.popularmechanics.com/technology/military_law/1227842.html

Give a logical explanation for the following pieces of conspiracy evidence:

Explain:

1. the concrete clouds of dust and collapsing building which looked like it was being demolished by explosives.
2. the seismic spikes.
3. why the steel did not need to melt for the buildings to collapse.
4. the small hole in the side of the Pentagon.
5. Find evidence to refute the report that the planes that hit the towers had no windows.