1. Для \(60^\circ\): \(\frac{60 \times \pi}{180} = \frac{\pi}{3}\) радиан.
2. Для \(72^\circ\): \(\frac{72 \times \pi}{180} = \frac{2\pi}{5}\) радиан.
3. Для \(-252^\circ\): \(\frac{-252 \times \pi}{180} = -\frac{7\pi}{5}\) радиан.
Ответ: \(\frac{\pi}{3}\), \(\frac{2\pi}{5}\), \(-\frac{7\pi}{5}\)