How do you calculate the circular base of an antenna? Can you provide an example? (The circle thing without the stick)

The cone in the diagram has the same height and base area as the prism. what is the ratio of the volume of the cone to the volume of the prism? h hl base area-b base area =b volume of cone_1 volume of prism 2 volume of cone 1 volume of prism 3 volume of cone 2 volume of prism 3 oc. od. volume of cone volume of prism e. volume of cone volume of prism 3 2