Can I delete my question on able2know after posting it?

There is a short window to delete it, but you may have passed that already.

The only threads that can be deleted (after a certain grace period of @5 minutes) are spam posts.

So, basically no. Moderators will edit out personal details if you are foolish enough to add them (phone numbers, addresses, etc...) in the first place.

So? It's not wise to ask pertinent homework or school test questions here if that's what you're worrying about.