Below is an context that describes a sql query, paired with an question that provides further information. Write an answer that appropriately completes the request.  # noqa: E501
### Context:
CREATE TABLE table_24399615_10 (episode_no VARCHAR, bbc_three_weekly_ranking VARCHAR, cable_rank VARCHAR)
### Question:
Which episode had bbc ranking and canle ranking of n/a?
### Answer:
SELECT COUNT(episode_no) FROM table_24399615_10 WHERE bbc_three_weekly_ranking = "N/A" AND cable_rank = "N/A"