1- a spot where id actually rather make a smaller turn bet rather than a big one. I'd fold.
2-fold pre, fold river
3-seems like quads, id call but can't justify it other than it seems like quads or air given he can't have too many 6x 4x.
4-don't like your c/r since he's utg. J on turn means you're now crushed pretty much (dont think too many ppl open AT utg nowadays). I'd just go c/c c/c, but as played fold turn