user: Question: On how many different dates did the episode with series number 35 air for the first time?
Columns: ['No. in series', 'No. in season', 'Title', 'Directed by', 'Written by', 'Original air date', 'Production code', 'U.S. viewers (millions)']
Types: ['text', 'text', 'text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['27', '1', '"True Concert"', 'Gary Halvorson', 'Dan Kopelman', 'November14,2009', '204', '3.8']
SQL:

assistant: SELECT COUNT("Original air date") FROM "Table" WHERE "No. in series" = '35';