Answers to my questions(7)

14 Are there any laws about music censorship?

There are currently no laws regarding music censorship.However I found out that according to the The first Amendment states ,CONGRESS SHALL MAKE NO LAW REPRESENTING AN ESTABLISHMENT OF RELIGION, OR PROHIBITING THE FREE EXERCISE THEREOF; OR ABRIDGING THE FREEDOM OF SPEECH, OR OF THE PRESS; OR OF THE RIGHT OF THE PEOPLE PEACEABLY TO ASSEMBLE, AND PETITION THE GOVERNMENT FOR A REDRESS OF GRIEVANCES.
it is illegal for government to censor the music, but it still ok for the organization like PMRC and private companies to censor the music. That's why the US government isn't interfere the music censorship directly.

Here is my source .
"Laws Regarding Music Censorship." . N.p., n.d. Web. 25 Jul 2012. <http://www.nku.edu/~issues/music_censorship/laws.htm>.

 15.What will happen if teenage listen too much rap/ rock music that contain dirty words , drug using and sexual expression?

 According to a 2006 study by the Pacific Institute for Research and Evaluation suggested that "young people who listen to rap and hip-hop are more likely to abuse alcohol and commit violent acts."

and another article  said that: "A 2008 study at North Carolina State University found that latent sexist attitudes were revealed in study participants regardless of whether they listened to rap music with sexist lyrics, or rap music with no sexist language."

 How ever I think that we can't blame all this bad behaviors to rap and rock music. teenage's behavior are mostly depend on the way their parents teach them.
so I think parents should be  responsible for their children's behavior.

source:
Valerie , Clark. "The Bad Effects of Rap Music on Teenagers Read more: The Bad Effects of Rap Music on Teenagers | eHow.com http://www.ehow.com/facts_4914950_bad-effects-rap-music-teenagers.html