Generally yes. However, you cannot engage in any illegal activity, with or without the parents permission, including physical contact that would be prohibited by law. Additionally, be aware, that depending on the age difference, you may still be in violation of the law, even with the parents permission. (For example, if you were a thirty year old man with a ten year old girl...this is child endangerment, and you and the parents could be prosecuted).
With parents permission.
Can they date? Yes, as long as the minor's parents give permission for it, because the parents of a minor have the right to determine who their child is and is not allowed to spend time with. Personally, I don't know any parents who would give permission for their 15-year-old child to date an adult, but maybe these parents would. Can they have sexual contact (which is not limited merely intercourse, by the way)? Absolutely not.
At 17 with parents permission.
If your question is: can an adult have sex with a minor when there are laws against it, then the answer is no, even if the minor's parents give 'permission' for it. No one has the right to give another person--including their own child--permission to break a law.
Yes but strictly with their parents permission
To date yes, but for sex the minor must have reached age of consent.
A person who takes in a minor with the parents' permission may face criminal charges. It is best to call the parents or the police if the minor refuses to leave.
If you are a minor you need your parents permission to move.
no
Even WITH parent permission, you cannot smoke as a minor. Under 0 circumstances can a minor smoke tobacco.
Not as long as you are a minor.
All of them. A minor needs parents permission in all the states.