Question(s) about precum?

A) What are the chances of me getting pregnant if I touch my vagina after having his precum on my hands?
B) Can a guy precum and then not come?
C) Can a guy stop himself from coming? Even whilst stimulation is being provided…a LOT?
D) How much time can there be between when the man releases precum and when he comes?
Thanks so much. I hope I’m not offending with this; it is explicit but I promise it’s purely for knowledge that I want to know this information.