Q. If the diameter of a sphere is increased by 20%, its surface area increases by:
✅ Correct Answer: (C)
44%
Explanation: Surface area ∝ d². (1.2)² = 1.44, so the increase is 44%.
Explanation by: Mahesh Chandra
Surface area ∝ d². (1.2)² = 1.44, so the increase is 44%.