I'm not really sure what a rearhistorical question is, but working on the principle that a circle is a crooked straight line bent so that the ends meet, it would appear they both stem from the same origin.
You can buy all you want, however you may not see any difference until you start using it
My point exactly!
Rhetorical question: A rhetorical question is a figure of speech in the form of a question posed for its persuasive effect without the expectation of a reply (e.g.: "Why me?) Rhetorical questions encourage the listener to think about what the (often obvious) answer to the question must be.....