Option D: 150°
Using Area of sector = $\dfrac{\theta}{360} \times \pi r^2$:
$60\pi = \dfrac{\theta}{360} \times \pi \times 144 \Rightarrow \theta = \dfrac{60 \times 360}{144} = 150°$
Apply the formula directly: Area = (θ/360) × πr². Substitute area = 60π and r = 12, then solve for θ. The π cancels, making calculation straightforward. Answer is 150°.