user: Question: What episode number in the series had 2.528 million u.s. viewers?
Columns: ['Overall', 'No. in series', 'Title', 'Directed by', 'Original air date', 'U.S. viewers (in millions)']
Types: ['real', 'real', 'text', 'text', 'text', 'text']
Sample row: [44.0, 1.0, 'Broke', 'Billy Corben', 'October2,2012', '2.528']
SQL:

assistant: SELECT "No. in series" FROM "Table" WHERE "U.S. viewers (in millions)" = '2.528';