1. Для \(20^\circ\): \(\frac{20 \times \pi}{180} = \frac{\pi}{9}\) радиан.
2. Для \(125^\circ\): \(\frac{125 \times \pi}{180} = \frac{25\pi}{36}\) радиан.
3. Для \(-36^\circ\): \(\frac{-36 \times \pi}{180} = -\frac{\pi}{5}\) радиан.
Ответ: \(\frac{\pi}{9}\), \(\frac{25\pi}{36}\), \(-\frac{\pi}{5}\)