In this clip, the professor is addressing the class as they are seated at their desks. The professor is explaining the format of the first exam. First, the professor discusses the group portion of the exam, explaining that each group turns in one copy, and everyone in the group receives the same grade. The professor then explains that he will randomly assign the groups and announce them on the morning of the exam. At the end of the clip, the professor explains the reasoning behind this decision is to ensure group accountability.
This clip takes place in week 12 (Practicing with Forces & Exam).