Answer: 282.6 square units
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Work Shown:
r = 3 is the radius of the circular base
h = 12 is the height of the cylinder
pi = 3.14 approximately
SA = surface area of the cylinder
SA = 2pi*r^2 + 2pi*r*h
SA = 2*3.14*3^2 + 2*3.14*3*12
SA = 282.6