We need the radius to find the surface area. Since we have the circumference we can use that to find the radius.
C = 2πr
23 = 2(3.14)r
23 = 6.28r
23/6.28 = r
3.66 = r
Now use the radius to find the surface area.
SA = 4πr²
SA = 4(3.14)(3.66)²
SA = 168.33
Surface area is C. 168 cm²
Hope this helps :)
