In the United Kingdom, what company has an unknown date and is an energy business?
CREATE TABLE "list_of_subsidiaries" (
  "date" text,
  "company" text,
  "business" text,
  "country" text,
  "value_usd" text
);
SELECT "company" FROM "list_of_subsidiaries" WHERE "business"='energy' AND "date"='unknown' AND "country"='united kingdom';