Explanation:
the area of the surface of a sphere is
4×pi×r²
with r being the radius. and the radius is half of the diameter.
in our case
r = 13/2 = 6.5 in
the surface is then
4×pi×6.5² = 4×pi×42.25 = 169pi =
= 530.9291585... in²
≈ 531 in²
Work Shown:
d = diameter = 13 inches
r = radius = d/2 = 13/2 = 6.5 inches
SA = surface area of a sphere
SA = 4*pi*r^2
SA = 4*3.14*(6.5)^2
SA = 530.66
SA = 531 square inches
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