Question

and we were this question

Answer 1

Sphere.  Mensuration.

Surface area = 4 π R² = 154 cm² (given)
                         R² = 154 * 7/(4*22) = 49/4 
                         R = 7/2 = 3.5 cm

Volume of sphere = 4/3 π R³  
                             = 4/3* 22/7 * 3.5³ cm³
                             = 179.67  or  179  2/3  cm³

Answer 2

Surface area of the sphere = 4πr^2

But it is given the surface area is 154 sq cm

So,
4πr^2 = 154
22/7 x r^2 = 154 ÷ 4
r^2 = 77/2 x 7/22
r^2 = 49/4
r = 7/2

Now, volume of a sphere = 4/3πr^3
= 4/3 x 22/7 x 7/2 x 7/2 x 7/2
= 539/3 = 179.67 sq cm

Hope This Helps You!