CREATE TABLE table_27615445_1 (episode_air_date VARCHAR, audition_city VARCHAR)

How many episode air dates are there for auditioning city Rio De Janeiro?
SELECT COUNT(episode_air_date) FROM table_27615445_1 WHERE audition_city = "Rio de Janeiro"
SELECT COUNT("episode_air_date") FROM "table_27615445_1" WHERE "Rio de Janeiro" = "audition_city"