Can you tell me the sum of Grid that has the Manufacturer of aprilia, and the sandro cortese?
CREATE TABLE table_47913 (
    "Rider" text,
    "Manufacturer" text,
    "Laps" real,
    "Time" text,
    "Grid" real
)
SELECT SUM("Grid") FROM table_47913 WHERE "Manufacturer" = 'aprilia' AND "Rider" = 'sandro cortese'
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: Can you tell me the sum of Grid that has the Manufacturer of aprilia, and the sandro cortese? ### Input: CREATE TABLE table_47913 (
    "Rider" text,
    "Manufacturer" text,
    "Laps" real,
    "Time" text,
    "Grid" real
) ### Response: SELECT SUM("Grid") FROM table_47913 WHERE "Manufacturer" = 'aprilia' AND "Rider" = 'sandro cortese'