What date did Dax Shepard play 20 questions?
CREATE TABLE "2012" (
  "date" text,
  "cover_model" text,
  "centerfold_model" text,
  "interview_subject" text,
  "20_questions" text,
  "pictorials" text
);
SELECT "date" FROM "2012" WHERE "20_questions"='Dax Shepard';