回複：謝謝小白兔！

all those civil cases have two judge.

A United States Magistrate Judge is a federal trial judge appointed to serve in a United States district court for a term of eight years. He or she is appointed by the life-tenured federal judges of a district court, District Judges, who supervise the activities of the Magistrate Judges by assigning civil cases for jury or non-jury trial upon consent of the parties and for pre-trial matters.

since those WOM will never go to trial, don't worry about Magistrate judge for now.

Remember: 1. all mails should be "certified mail", priority will be rejected.
2. once mail anything to defendants, always send the "certificate of service" back to court.