Find the total surface area of a solid sphere of radius 3.5 cm. (Take π = 22/7)
Answer and explanation
Correct answer: B. 154 cm²
- Step 1: Surface area of sphere formula: A = 4π r². Step 2. Substitute values: A = 4 × (22/7) × (3.5)² = 4 × (22/7) × 12.25 = 4 × 22 × 1.75 = 88 × 1.75 = 154 cm². Answer: 154 cm². Why not the others: 308 cm² doubles the area; 77 cm² divides by 2; 231 cm² is for a hemisphere plus base.
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