what are the total km for this xhart
CREATE TABLE table_204_763 (
    id number,
    "county" text,
    "km" number,
    "intersecting road" text,
    "notes" text,
    "coordinates" text
)
SELECT SUM("km") FROM table_204_763
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 are the total km for this xhart ### Input: CREATE TABLE table_204_763 (
    id number,
    "county" text,
    "km" number,
    "intersecting road" text,
    "notes" text,
    "coordinates" text
) ### Response: SELECT SUM("km") FROM table_204_763