Mastubation

Mufti-saab when I was going through your questions I read that masturbation is haraam. I did not know this previously. I used to commit this sin and make wudhu and read Salaat. Is my salaat accepted? Do you have to make ghusl after you commit this sin? If my salaat is not accepted how do I make up for it?

Does a girl only become baligh when she first menstruates? I heard that there are other things that make a girl baligh. Can Mufti-saab please explain.

Jazakallah