Android Studio appcompat and firebase Version failing

Question

I have a Problem with Android Studio or Android itself (?). I want to include ad Mob in my App and followed the instructions on the Android Developer site. So my Problem is that I can't compile firebase as shown on the picture: with firebase

This happens only if I add this specific firebase line as shown in the other screenshot. without firebase

Has anyone a solution for this?

Answer 1

Suggested changes:

compileSdkVersion 25
...
compile 'com.android.support:appcompat-v7:25.3.1'