Word Problem With Bridges and People?

Okay, every time two people cross, one must go back. So Abe must go back every time, because he is fastest. So 85 for Frank and Abe, 20 for Abe, 65 for Erica and Abe, 20 for Abe, 60 for Darlene and Abe, 20 for Abe, 35 for Carlos and Abe, 20 for Abe, 25 for Betty and Abe. 350 minutes, or 5 hours 50 minutes.