CREATE TABLE table_36731 ("Year" TEXT, "Champion" TEXT, "Runner-up" TEXT, "Score" TEXT, "Surface" TEXT)

What is the score of champion Ken Rosewall in 1957?
SELECT "Score" FROM table_36731 WHERE "Champion" = 'ken rosewall' AND "Year" = '1957'
SELECT "Score" FROM "table_36731" WHERE "Champion" = 'ken rosewall' AND "Year" = '1957'