1) If I buy a license for Android for $ 400, I can sell the game on GooglePlay? Although I Unity3D Free Version! 2) In PlayGoogle need a license nor less than 50 years, and for how many years Unity3D grants a license for $ 400? Thank you!
Yes, you can release android games on the android market/play/whatever they turn it into with the $400 license, even if you only use the free version of regular unity. The license is never ending for that version (If you buy an unity 3 license, you can use unity 3 to create games indefinitely)
Of course you can sell your game on Play Store. But don't forget that you need to pay another $25 to put your games on Android market (Play Store).