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The red figure  will just have  the surface area  of a sphere  of  radius  r

So....its surface area  is     4pir^2

The height of the cylinder  = 2r

So......its surface area  is   [ 2pi (r^2)  +  2pi*r (2r) ]   =   [ 2pi(r^2)  + 4pir^2 ]

So   the cylinder has the greater surface area

The red figure at the right is made of two hemispheres of equal radius. The blue cylinder at the left has the same radius and height as the red figure.

Which shape has a larger surface area?