Continuity mistake: In one scene the clock radio is set to 20:07 and in the next it is 8:07 right before it turns into counting down the 60 minutes. (00:34:15 - 00:38:00)
Visible crew/equipment: When he is fixing the crooked ship picture in the somewhat dark room in the reflection behind him you see an arm with a light blue short sleeve shirt in the glass door.
Continuity mistake: When he enters the room he flips up the first 2 lights. After he shuts the door the 1st and 3rd switch are up and the 2nd is down.
Chosen answer: He sums up the individual numbers: 1+4+0+8 = 13.
Twotall