How is eccentricity defined? Group of answer choices The ratio of the distance of the foci to one astronomical unit. The ratio of the distance between perihelion and the Sun to the distance between aphelion and the Sun. The ratio of the length of the semi-minor axis to the length of the semi-major axis. The ratio of the length of the major axis to the distance between the foci. The ratio of the distance between the foci to the length of the major axis