A cone is placed inside a cylinder as shown. The radius of the cone is half the radius of the cylinder. The height of the cone is equal to the radius of the cylinder. what is the volume of the cone in terms of the radius, r?
OA. V=1/3πr²h
OB. V=1/6πr²
OC. V=1/12πr³
OD. V=2πr³