Mensuration IGCSE

Find the radius, first.....so we have

356 = (4/3) * pi * r^3       divide both sides by  (4/3) pi

[ 356 ]  / [(4/3)pi]  = r^3     simplify 

[267 /pi]  = r^3       take the cube root of both sides

[257/pi]^(1/3)   = r

Surface area  =  4*pi * r^2  =

4 * pi * ( [257/pi]^(1/3) )^2  ≈  236.81 cm²

A sphere has a volume of 356 cm3. Calculate the surface area of the sphere. pls help