Which definitions of the MyInterface interface are

Which definitions of the MyInterface interface are correct?

 interface MyInterface { int result(int i,int j); }

 public interface MyInterface { public int result(int i,int j); }

 public interface MyInterface { public abstract int result(int i,int j); }

 public interface MyInterface { public int i; public int result(int i,int j); }

 public interface MyInterface { public int i=0; public int result(int i,int j); }

 interface MyInterface { public int result(int i,int j) { return(i+j); } }

Explanation

All declared methods are public in intefaces, public keyword is optional. Abstract keyword is optional too. As they are applied by default, they are redundant and should not be explicitly declared.
Interface fields are constants and have to be initialized.
Interfaces can have method definitions but methods myst be declared with default keyword.