General College of Engineering (ENG) questions......

With the recent BU Portal opening and the paranoia about these things, these are the following questions:

1. New Student Housing Application: If I haven't found a roommate but completed the application, will BU put me with a random roommate based on my circumstances?
2. Engineering Diagnostic Exam (EDE): I know this is mandatory.... however as paranoid as I am right now, is there any study guide or a practice exam I can use to help me practice for this exam?
3. University Orientation: For the BU Orientation, is it mandatory for students to have to go to in person for the orientation or can I do it virtually over zoom?
4. In the View Financial Aid, it states the Remaining Need, which is basically another saying for what you need to pay?