table: 1-11253290-2
columns: #, Episode, Rating, Share, Rating/Share (18-49), Viewers (millions), Rank (timeslot), Rank (night), Rank (week)
Q: How many viewers (millions) were there for rank (week) 20?
A: SELECT COUNT Viewers (millions) FROM 1-11253290-2 WHERE Rank (week) = '20'