(d) $S = \left( 4 \times 1.5 + 4 \times 1.5 + \frac{1}{2} \times 10 \times 1.5 \times 1.5 \right)$m $= (6 + 6 + 5 \times 2.25)$m = 23.25m
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.