Answer: 7cm
Explanation:
The surface area of a sphere is calculated by using the formula:
A = 4πr²
Since the surface area is 616cm², using the formula given, the radius will be calculated thus:
A = 4πr²
616 = 4 × 22/7 × r²
616 = 88/7 × r²
Multiply both side by 7/88
616 × 7/88 = 88/7 × 7/88 × r²
49 = r²
r = ✓49
r = 7
The radius is 7cm
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