A complete exam paper — six exercises, ninety minutes — taken at home under exam conditions, then corrected together in class. It does not count. It is the most useful ninety minutes of the semester, because it is the only way to find out what the two hand-written sheets need to contain.
When this week is written, each exercise below becomes a form on this page and a slide in the deck, generated from one array so the two can never disagree — and its solution opens when the instructor reveals it in class. Same engine as Weeks 1–2 (exercises.js).