private twitter?????

[Kiari]

I'm new to twitter so I have a few questions. If my twitter is private and I tweet someone who's twitter isn't private (and they are NOT following me) will they be able to see my tweet even if i use @- then their user name?
What about when I hashtag something and my twitter is private, can anyone see that tweet that isn't following me?

[Barbie]

Your hashtag tweets can only see by your followers, no other can see it. If you tweet using @username then they can see it.