I could go either way on these...I'm leaning toward
1 - fold
2 - (w/ no read, usually call pf) ummm fold with no read.
3 - bet 20-30 on river, you look like a scared Ax. prob fold as played, not sure though.
4 - absolutely no reads? close one...I guess fold
5 - no reads again? got to call now. I might call flop, reevaluate turn by card and bet size...