A cone has a diameter of 6 centimeters and a height that is 3 times the diameter. Using 3.14 for pi, which of the following can be used to calculate the volume of the cone?

one over three(3.14)(3cm)2(18cm)
one over three(3.14)(6cm)2(18cm)
one over three(3.14)(18cm)2(3cm)
one over three(3.14)(18cm)2(6cm)