CREATE TABLE table_64231 ("Week" FLOAT, "Date" TEXT, "Opponent" TEXT, "Result" TEXT, "Attendance" FLOAT)

Who was the opponent on November 15, 1981?
SELECT "Opponent" FROM table_64231 WHERE "Date" = 'november 15, 1981'
SELECT "Opponent" FROM "table_64231" WHERE "Date" = 'november 15, 1981'