Speak with rhetorical questions

On the surface, rhetorical questions appear in the form of questions, but in fact they express affirmative meaning, and the answer lies in the questions.

1, I don't know? I know about it.

2. Am I so stupid? I'm not that stupid.

Don't you think this is wrong? You should think this is wrong.

4. How can you do this? You can't do this.

5. Can we waste time? We can't waste time.

6. How can you destroy the environment? You can't destroy the environment.