If you say that you do not participate in open source projects, then you cannot complete the survey because the required questions at the bottom are not appropriate.
I am guessing it was done on purpose, but mentioning it just in case.
An office of about five employees seems optimal to me, normal office desks - no cubicles for people to hide in. Ringing phones need to be kept to a minimum for development though, as they are too distracting.
I am guessing it was done on purpose, but mentioning it just in case.