Use these passwords to unlock levels:
2 = Batman, Batmobile, Batman, Batcycle
3 = Batman, Batcycle, Batgirl, Batcycle
4 = Batmobile, Batmobile, Batman, Batmobile
5 = Batmobile, Batcycle, Batgirl, Batgirl
6 = Batcycle, Batcycle, Batman, Batgirl
7 = Batcycle, Batgirl, Batgirl, Batman
8 = Batgirl, Batcycle, Batman, Batmobile
9 = Batgirl, Batgirl, Batmobile, Batcycle