low-bearing walls. walls that are two feet in thickness, and are impregnated with 70 tons of steel reinforcing parts per floor and makes the shield walls and core of the building impregnable. and first responders, we see the black poles with the yellow stripes along the side and down here and there is another one back here, these are all for communications, for fire and police. well, you also have an addition, you have the sprinkler system, see the red pipe, it is a sprinkler system, that is designed to work under any circumstances. because, it is within the core wal walls. on 9/11 the plane sheered through the sprinkler system and these are all incorporated into the buildings and built to a totally different standards than has ever existed . you can t get back what was lost that day but if we can move forward and rebuild, i am glad