
Bradford T. answered 11/16/21
Retired Engineer / Upper level math instructor
1) A full circle of arc length 2π radians has and area of πr2. We can form a ratio:
2π/(π/6) = πr2/(16π/3)
12 = 3r2/16
r = √(16•12/3) = 8 in
2) Arc length, S = rθ
θ = S/r = (10π/3)/10 = π/3 radians or 60°