What is the Date, when the Year is after 1978, and when the Location is Memorial Stadium (Baltimore)?
CREATE TABLE "1970s_colts_11_9" (
  "year" real,
  "date" text,
  "winner" text,
  "result" text,
  "loser" text,
  "location" text
);
SELECT "date" FROM "1970s_colts_11_9" WHERE "year">1978 AND "location"='memorial stadium (baltimore)';