If the net was folded into a cylinder, the length of the rentangle would be the circumference of the circle since it wraps around it.
C = 2pi*r
So 2pi*3 = 6pi
Then multiply by the height to get 84pi
Then the area of a circle is pi*r^2
We have two circles so 2 * pi * 3^2 = 18pi
Add to get 84pi + 18pi = 102pi.
