What was the challenge for episode 28?
CREATE TABLE table_24798489_2 (
    challenge VARCHAR,
    episode_number VARCHAR
)
SELECT challenge FROM table_24798489_2 WHERE episode_number = 28
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: What was the challenge for episode 28? ### Input: CREATE TABLE table_24798489_2 (
    challenge VARCHAR,
    episode_number VARCHAR
) ### Response: SELECT challenge FROM table_24798489_2 WHERE episode_number = 28