CREATE TABLE table_28794 ("Episode" FLOAT, "First broadcast Denmark  (  DR1  ) " TEXT, "Official TNS Gallup ratings" FLOAT, "First broadcast UK  (  BBC Four  ) " TEXT, "Official BARB ratings" FLOAT)

When was the first UK broadcast when the official Barb ratings was 1085000?
SELECT "First broadcast UK ( BBC Four )" FROM table_28794 WHERE "Official BARB ratings" = '1085000'
SELECT "First broadcast UK ( BBC Four )" FROM "table_28794" WHERE "Official BARB ratings" = '1085000'