There are 30 cars in my building's parking lot. All of the cars are red or white, and a car can have either 2 doors or 4 doors. of them are

There are 30 cars in my building's parking lot. All of the cars are red or white, and a car can have either 2 doors or 4 doors.  of them are red,  of them are 4-door, and 8 of them are 2-door and white. How many of the cars are 4-door and red?