Where to find informations about theoric questions
I'm training to pass the Dev certification and for certain questions, it is really impossible to find the answer and a documentation appropriate to the question.
For example :
After hours of searches in the documentation, I can't really find anything on these questions. These are only examples but there are really too many questions that aren't documented.
Why just don't give the answers at the end of the tests certifications ? How can we improve without knowing the answers ?
Can you at least tell me where to find the documentation to these questions if you can't give me the answer ?