Question: What's the original air date of the episode with production code 2T6719?
SQL: SELECT "Original air date" FROM "1-12159115-2" WHERE "Production code" = '2T6719';

Question: Who's the writer of the episode see by 12.13 million US viewers?
SQL: SELECT "Written by" FROM "1-12159115-2" WHERE "U.S. viewers (millions)" = '12.13';

Question: What's the total number of episodes with production code 2T6705?
SQL: SELECT COUNT("Title") FROM "1-12159115-2" WHERE "Production code" = '2T6705';

Question: What's the total number of directors who've directed episodes seen by 11.34 million US viewers?
SQL: SELECT COUNT("Directed by") FROM "1-12159115-2" WHERE "U.S. viewers (millions)" = '11.34';

Question: What's the production code of the episode seen by 11.64 million US viewers?
SQL: SELECT "Production code" FROM "1-12159115-2" WHERE "U.S. viewers (millions)" = '11.64';