Translate the following question to SQL: What are the average, maximum and total revenues of all companies?

Schema: CREATE TABLE Manufacturers (
    Code INTEGER   PRIMARY KEY,
    Name VARCHAR(255) NOT NULL,
    Headquarter VARCHAR(255) NOT NULL,
    Founder VARCHAR(255) NOT NULL,
    Revenue REAL
);

CREATE TABLE Products (
    Code INTEGER   PRIMARY KEY,
    Name VARCHAR(255) NOT NULL,
    Price DECIMAL NOT NULL,
    Manufacturer INTEGER NOT NULL,
    FOREIGN KEY (Manufacturer) REFERENCES Manufacturers(Code)
);
user
SELECT avg(revenue) ,  max(revenue) ,  sum(revenue) FROM manufacturers
assistant