what is the average shot volume (cm 3) when the shot diameter (cm) is less than 6.04?
CREATE TABLE table_47437 (
    "gun class (pdr.)" real,
    "shot diameter (cm)" real,
    "shot volume (cm 3 )" real,
    "approx. service bore (cm)" real,
    "mass of projectile (kg)" real
)
SELECT AVG("shot volume (cm 3 )") FROM table_47437 WHERE "shot diameter (cm)" < '6.04'
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 is the average shot volume (cm 3) when the shot diameter (cm) is less than 6.04? ### Input: CREATE TABLE table_47437 (
    "gun class (pdr.)" real,
    "shot diameter (cm)" real,
    "shot volume (cm 3 )" real,
    "approx. service bore (cm)" real,
    "mass of projectile (kg)" real
) ### Response: SELECT AVG("shot volume (cm 3 )") FROM table_47437 WHERE "shot diameter (cm)" < '6.04'