/// <summary> /// 1/3 (Base x Height) /// </summary> /// <returns></returns> public virtual Volume CalculateConicalVolume() { if (!Height.IsSpecified || !Girth.IsSpecified) { return(Volume.Null()); } double radius = (double)Girth.Feet / Math.PI / 2.0; return(Volume.CalculateConical(radius, Height.Feet)); }