It will be just that much better for both of you. 1) Fireman saying there was "a hole 20 stories tall in the building, with fire on several floors." "I would say it was probably about a third of it".
3) They put a transit on it and afterward were "pretty sure she was going to collapse." 4) They "saw a bulge in the southwest corner between floors 10 and 13". The DC of this check is 25, or the result of the captains Profession (sailor) check, whichever is higher.