It is the same in English. Changing the intonation on a statement can turn it into a question-usually when it is something you are incredulous about...HE is a rocket scientist? Or, you can switch the word order and it assumes you are merely trying to clarify facts...Is he a rocket scientist?
First, it has question marks so it's asking a question. Second, Duolingo gave me a hint and said that when it's asking a question, you'd technically put it as a statement. What makes it a question is if you use your voice like you're asking a question or put question marks. Sorry if that didn't make any sense.