Find the surface area of a hand held fan (modeled with negligible depth) with radius 8 cm and a 60 degree angle at the centre
60 degrees = π/3 radians
A = 1/2r2θr = 8θ = π/3
1/2 x 82 x π/3 = 33.5103216... cm233.5103216... x 2 = 67.0 cm2 to 3 s.f.
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