1.  Base radius of the frustum cone is  r = 3.5 cm.

    The upper radius of the frustum cone is  R = 7 cm.

    The height of the frustum of the cone is  h = 21 - 7 = 14 cm.

    The slant height of the frustum of the cone is  s =  =  = 14.43 cm  (approximately).



2.  The latent surface of the frustum of the cone is  

     =  =  = 476.19 square centimeters.

       (regarding this general formula see the link http://mathworld.wolfram.com/ConicalFrustum.html )



3.  The surface area of the semi-sphere is   =  =  = 308 square centimeters.


4.  The area of the base is   =  =  = 38.5 square centimeters.



5.  The answer to the problem question is the sum  


     +  +  = 476.19 + 308 + 38.5 = 822.69 square centimeters.