CREATE TABLE table_6291 ("Player" TEXT, "Result" TEXT, "Appeared" FLOAT, "RR W\\u2013L" TEXT, "RR W Rate" FLOAT)

For Angelique Kerber who had an RR Rate of less than 0.33, what's the appeared?
SELECT SUM("Appeared") FROM table_6291 WHERE "RR W Rate" < '0.33' AND "Player" = 'angelique kerber'
SELECT SUM("Appeared") FROM "table_6291" WHERE "Player" = 'angelique kerber' AND "RR W Rate" < '0.33'