after the planes crashed into the north tower at 9:00 a plane crashed the south tower and at 9:56 the south tower collapesed

that is the south tower collapsing at 9:56 am and at 10:06

that’s the north tower collapsing at 10:06 am and the 7th world trade center collapsed at 5:21 because of the heavy debris from the north tower and fires and the staff from the building hitting it

that is the 7th world trade center collapsing at 5:21 and it was next to the north tower