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_name_91 (winning_driver VARCHAR, winning_constructor VARCHAR, date VARCHAR)
### Question:
Name the Winning driver of mercedes on 22 august?
### Answer:
SELECT winning_driver FROM table_name_91 WHERE winning_constructor = "mercedes" AND date = "22 august"