How many viewers watched the episode with a story by david simon & mari kornhauser?
CREATE TABLE "table1_26914076_3" (
  "no" real,
  "num" real,
  "title" text,
  "directed_by" text,
  "story_by" text,
  "teleplay_by" text,
  "original_air_date" text,
  "u_s_viewers_millions" text
);
SELECT "u_s_viewers_millions" FROM "table1_26914076_3" WHERE "story_by"='David Simon & Mari Kornhauser';