Please don't use the word "retarded" like this. If you suspect you're asking a question with an obvious answer that you've missed, try saying "forgive my ignorance" instead.
There's nothing wrong with asking questions without self-deprecation, but if you're going to self-deprecate, try not to use hurtful language.
There's nothing wrong with asking questions without self-deprecation, but if you're going to self-deprecate, try not to use hurtful language.