CREATE TABLE table_640 ("Episode #" FLOAT, "Title" TEXT, "Part 1" TEXT, "Part 2" TEXT, "Part 3" TEXT, "Part 4" TEXT, "Part 5" TEXT, "Part 6" TEXT)

When did the part 1 of the episode 'Anxiety' air?
SELECT "Part 1" FROM table_640 WHERE "Title" = 'Anxiety'
SELECT "Part 1" FROM "table_640" WHERE "Title" = 'Anxiety'