Girls, what would you do if a random guy said "hey" on Facebook?

You two have never met and and only have a few mutual friends?

Also please list your age and any stories you know of that something like this has happened.
I would not reply
I would say "hey" back
I would say "how do I know you?"
I would say "its kinda weird that I don't know you"
Select gender and age to cast your vote:
Girls, what would you do if a random guy said "hey" on Facebook?
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