Name the hull number of Commissioned– Decommissioned of 1973–1996
CREATE TABLE "ships" (
  "ship" text,
  "hull_no" text,
  "builder" text,
  "home_port" text,
  "commissioned_decommissioned" text,
  "nvr_page" text
);
SELECT "hull_no" FROM "ships" WHERE "commissioned_decommissioned"='1973–1996';