CREATE TABLE table_5842 ("Race" TEXT, "Length" TEXT, "Class" TEXT, "Circuit" TEXT, "Date" TEXT)

On what date did Contac 12 Hours of Sebring take place?
SELECT "Date" FROM table_5842 WHERE "Race" = 'contac 12 hours of sebring'
SELECT "Date" FROM "table_5842" WHERE "Race" = 'contac 12 hours of sebring'