all of it and such a long road ahead, thank you all are have much for starting us off this hour. we really appreciate it. joining me for more on the investigation into the collapse is aaron hillsheimer his company investigated the pentagon after the 9/11 terror attacks and has been hired to work with those down in surfside. sir, thank you so much for being with us today. each day the mayor of miami-dade is being pressed on what caused this collapse, but we don t have a definitive answer yet. how much work can be done to try and find an answer to that question while the search and rescue operation is under way? we ve been working since friday after the collapse in doing all of the things we can do without physically being on the pile in the debris. we re doing computer models of the building based on the original drawings that we have. we re comparing those results to