how many winners were in round 8
CREATE TABLE table_15511178_3 (
    winning_driver VARCHAR,
    rd VARCHAR
)
SELECT COUNT(winning_driver) FROM table_15511178_3 WHERE rd = 8
Below are sql tables schemas paired with instruction that describes a task. Using valid SQLite, write a response that appropriately completes the request for the provided tables. ### Instruction: how many winners were in round 8 ### Input: CREATE TABLE table_15511178_3 (
    winning_driver VARCHAR,
    rd VARCHAR
) ### Response: SELECT COUNT(winning_driver) FROM table_15511178_3 WHERE rd = 8