user: Question: Name who wrote the episode when the viewers was 1.81
Columns: ['No. in series', 'No. in season', 'Title', 'Directed by', 'Written by', 'Original air date', 'U.S. viewers (million)']
Types: ['text', 'text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['100-101', '1-2', '"The Blueprint"', 'Salim Akil', 'Mara Brock Akil', 'March26,2013', '2.54']
SQL:

assistant: SELECT "Written by" FROM "Table" WHERE "U.S. viewers (million)" = '1.81';