Why should we declare interface methods as public? [duplicate]

Answer 1

1. If we mark a interface method as private the implementing class wont see the method and cant override it.

2. If we mark a interface method as protected the implementing class wont see the method unless it is in the same package as the interface.

3. If we mark a interface method without any access modifier the
   implementing class wont see the method unless it is in the same
   package as the interface