What is the highest number of not usable satellites when there are more than 0 launch failures, less than 30 retired, and the block is I?
CREATE TABLE table_40906 (
    "Block" text,
    "Launched" real,
    "Operational" real,
    "Not usable" real,
    "Retired" real,
    "Launch Failures" real
)
SELECT MAX("Not usable") FROM table_40906 WHERE "Launch Failures" > '0' AND "Retired" < '30' AND "Block" = 'block i'
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 highest number of not usable satellites when there are more than 0 launch failures, less than 30 retired, and the block is I? ### Input: CREATE TABLE table_40906 (
    "Block" text,
    "Launched" real,
    "Operational" real,
    "Not usable" real,
    "Retired" real,
    "Launch Failures" real
) ### Response: SELECT MAX("Not usable") FROM table_40906 WHERE "Launch Failures" > '0' AND "Retired" < '30' AND "Block" = 'block i'