4
If the cylinder is open it means there is no area of the top
So the surface of cylinder would be lateral surface and base area
[tex]A=2\pi rh+\pi r^2\\\\A=2\pi\cdot4\cdot7+\pi\cdot4^2=56\pi+16\pi=72\pi\approx72\cdot3,14=226,08[/tex]
5
If the cylinder is close it has two areas of base
[tex]A=2\pi rh+2\pi r^2\\\\A=2\pi\cdot10\cdot9+2\pi\cdot10^2=180\pi+200\pi=360\pi\approx360\cdot3,14=1130,4[/tex]
