CREATE TABLE table_name_89 (time INT, year VARCHAR, event VARCHAR)

What is the greatest Time with a Year of 1991, and Event of 4x100 m relay?
SELECT MAX(time) FROM table_name_89 WHERE year = 1991 AND event = "4x100 m relay"
SELECT MAX("time") FROM "table_name_89" WHERE "4x100 m relay" = "event" AND "year" = 1991