1.Is Russian an international language?
2.In what countries do people speak Russian?
3.Why is it important for teenagers from other countries to learn Russian?

1.Yes, it is.Russian was, still is and will be international language from times of tsarist Russia until now.
2.People speak Russian in all republics of former USSR. But in recent time in order to avenge and humiliate Russia ultra-nationalists in Baltic Countries, Ukraine and Georgia try to eradicate Russian from an orb of international communication.
3. It's important for teenagers from other countries to learn Russian because in result of this learning they will be able to speak with Russian fellows and other people of Russia directly, and overcome thus different myths which make difficult mutual understanding.

1. Yes, Russian language is an international language because more than 300 million people speak it.
2. In Russia and in the CIS countries.
3. Russian language is very rich and will allow you to feel comfortable in countries where the language is spoken.