Continuity mistake: When Elliot is unpacking her books at the apartment, she places a brown book on top of the pile next to her. In the next shot, there is a green book on top of the pile.
Continuity mistake: The second time that Turk and Elliot are studying in the apartment, papers appear on the table in front of Elliot from nowhere.
Answer: Dan was drinking beer and Cox feared that Dan might get so intoxicated he would fall asleep and drown in the tub.
Mortug