What is the surface area of a sphere with a radius that is half the diameter of a circle with a circumference of 31.4 units?
Category: Math · Difficulty: expert
Hint: Recall the formula for surface area of a sphere.
Answer
31.4π
Explanation
The radius calculated from the circumference gives us the radius to use in the surface area formula, A = 4πr².
This is a expert math riddle — one of the harder riddles here. The answer is 31.4π.
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