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

Let radius=r, Surface Area=154cm² ⇒4πr²=154 ⇒r²=154×7/22×4 ∴r=7/2=3.5cm
Volume of sphere=4/3πr³=4/3×22/7×3.5×3.5×3.5=179.66cm³