how many lower yazoo phases are there ?
CREATE TABLE table_203_645 (
    id number,
    "lower mississippi periods" text,
    "lower yazoo phases" text,
    "lower yazoo\ndates" text,
    "tensas/natchez phases" text,
    "cahokia phases" text,
    "cahokia dates" text,
    "ohio/miss. river\nconfluence phases" text,
    "ohio/miss. dates" text
)
SELECT COUNT(DISTINCT "lower yazoo phases") FROM table_203_645
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 lower yazoo phases are there ? ### Input: CREATE TABLE table_203_645 (
    id number,
    "lower mississippi periods" text,
    "lower yazoo phases" text,
    "lower yazoo\ndates" text,
    "tensas/natchez phases" text,
    "cahokia phases" text,
    "cahokia dates" text,
    "ohio/miss. river\nconfluence phases" text,
    "ohio/miss. dates" text
) ### Response: SELECT COUNT(DISTINCT "lower yazoo phases") FROM table_203_645