The diagram below represents a cone of height 12cm and a base radius of 9cm from which a similar smaller cone is removed, leaving a conical hole of height 4 cm. (a). calculate: (i) the base radius of conical hole. (ii). The volume, terms of #pi#, of the smaller cone that was removed.(b) (i) determine slant height of the original cone.ii). Calculate, in terms of #pi#, the surface area of the remaining solid after the smaller cone is removed.