Question

When a class both extends and implements, by convention the ____ clause follows the extends clause in the class header?

Answer 1

The correct answer is implements.
In the case where there are both the implements and the extends clause present in the class header, the convention is that the first one should be the implements clause, followed by the extends clause.
This makes sense because you first need to implement the meaning you want to talk about, and then you will extend upon it later.