How to calculate the area and perimeter of a Ring using C++ Structures?

How to calculate the area and perimeter of a ring using C++ Structures ?

internal: center = (1.2, 6.5), radii = 2.8; external: center = (1.2, 6.5), radii = 5.4

struct Point
{
    float x;
    float y;
};

struct Circle
{
    Point center;
    float radii;

    float Area() { return 3.14f * radii * radii; }
    float Perimeter() { return 2.0f * 3.14f * radii; }
};

struct Ring
{
    Cricle external;
    Circle internal;

    float Area() { return external.Area() - internal.Area(); }
    float Perimeter() { return external.Perimeter() + internal.Perimeter(); }
};