Because 7 8 9.
It doesn't have windows.
Because Windows 7, 8 9.....
Because 7 ate(8) 9!
9 out of 10 zombies said "braaaaiiiiinnnnssss" number 10 ate the researcher.
Nothing because ghosts don't exist. Edit:Holy crap I just realized I didn't post this on /r/antijokes.
Gingerly.
Because 7 8 9 A
Because 7 8 9. (7 ate 9)