If it is a closed cylinder, total surface area of Cylinder A = [tex]2\pi r^2h[/tex] + [tex]2 \pi rh[/tex] = [tex]2 \pi r(r+h)[/tex], while surface area of cylinder B is [tex]2 \pi (2r)(2r+2h) = 8 \pi r(r+h)[/tex]. Therefore, dividing B by A, the surface area of B is 4 times greater than A.
