First of all, a 30yo woman is not a girl, she an adult/grownup woman.The both of you have been able to marry whoever you want since you were 18. So yes!
depends on where the girl lives......
If she wants to.
Yes, if they have the permission of the girl's parents.
Yes.
No this is against the law.
If the girl has parental consent, yes.
If she is 18 years or older, yes she can. Or if her parents sign, she can.
Not without parental permission. Lucky man, poor girl.
Yes she can.
If she has parental permission.
In the US she can marry if she has parental permission. Otherwise she must be at least 18.
Yes, she can.