SELECT COUNT(*) FROM table_204_561 WHERE "handicap (st-lb)" = '10-0'
tell me the number of horses with a 10-0 handicap .
CREATE TABLE table_204_561 (
    id number,
    "fence" number,
    "name" text,
    "jockey" text,
    "age" number,
    "handicap (st-lb)" text,
    "starting price" text,
    "fate" text
)