Question

Please help, thank you.

Answer 1

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 :)