As the others stated, no, don't cross post. Each site has a specific area that it covers. For instance, programmers stackexchange site covers conceptual questions about software development. This is where your questions belongs. Stackoverflow is more meant for specific programming problems. I admit, it's easy to get confused but thoroughly reading their about pages clear things up.
Worse comes to worse it gets migrated. If you feel like you posted in the wrong area, ask a moderator to migrate it (flag it, click other, and ask to move it to another site) or delete your questions and re-post it.