Asking questions on Twitter?

[Michael M]

Okay, so I'm following someone I don't "know" on Twitter. Let's call her...Sally.
Now, I'm following Sally, and Sally has put up a Twit (is that what they're called? Singular?) Now, I've replied to that, however I know that Sally isn't following me. If Sally isn't following me, she won't get my reply right?
So, if everything I just said is correct, then how do I ask Sally my question? Do I have to find a way to get her to follow me or is there a way around this? I'm not entirely familiar with how twitter works aside from the basics.

Thanks in advance.