Find the volume of a sphere whose surface area is 154 cm².

Given: surface area of sphere = 154 cm²

We know that, the surface area of the sphere = 4πr²

4 × (22/7) r² = 154 

r² = (154×7)/(4 ×22)

r = 7/2

The radius is 7/2 cm

We know that volume of the sphere = (4/3) πr³

Substituting the values, 

V = (4/3) × (22/7) × (7/2)³

V = $179 \frac{2}{3}$cm³