CREATE TABLE table_name_75 (date VARCHAR2, opponent VARCHAR2, score VARCHAR2)

When was the event that had Liberia as an opponent and resulted in a 1-0 score?
SELECT date FROM table_name_75 WHERE opponent = "liberia" AND score = "1-0"
SELECT "date" FROM "table_name_75" WHERE "1-0" = "score" AND "liberia" = "opponent"