The formula for the Total surface area of a cylinder is 56.52m^2,
This is,
[tex]2\pi r(r+h)=56.52[/tex]r=3 , so
[tex]\begin{gathered} 2\times\pi\times2(2+h)\text{ = 56.52} \\ 12.57(2+h)=56.52 \\ 2+h=\frac{56.52}{12.57}=\text{ 4.5} \end{gathered}[/tex]So h = 4.5 - 2 = 2.5 meters.
h= 2.5 meters