In a right circular cone, the cross section made by a plane parallel to the base is a
(a) sphere (b) hemisphere (c) circle (d) a semicircle
(c) circle
Q7. The height and the radius of the base of a right circular cone are 12 cm respectively. The radius of the circular cross-section of the cone cut by a plane parallel to its base at a distance of 3 cm from the base is