What is the total surface area of a solid sphere of radius 3.5 cm? (Take pi = 22/7)
Answer and explanation
Correct answer: B. 154 cm^2
- Step 1: Surface area formula for a sphere: Area = 4 pi r^2. Step 2. Substitute r = 3.5 = 7/2: Area = 4 (22 / 7) (7/2)^2 = 4 (22 / 7) (49 / 4) = 22 7 = 154 cm^2. Answer: 154 cm^2. Why not the others:* 77 cm^2 divides by 2; 308 cm^2 doubles the area; 231 cm^2 is hemisphere surface area plus base.
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