The arc length of a subtending arc on a circle has the formula: s = r<span>θ where is the arc length r is the radius </span><span>θ is the angle subtended </span> So, θ = s/r = 8π / 4.5 = 16<span>π/9
We multiply it with 180/</span><span>π to convert it to degrees. </span>(16π/90) (180/π) = 320<span>°</span>