1. **Convert degrees to radians using the formula:** $$\text{Radians} = \text{Degrees} \times \frac{\pi}{180}$$ **a)** For 30°: $$30 \times \frac{\pi}{180} = \frac{30\pi}{180} = \frac{\pi}{6}$$ **b)** For 60°: $$60 \times \frac{\pi}{180} = \frac{60\pi}{180} = \frac{\pi}{3}$$ **c)** For 180°: $$180 \times \frac{\pi}{180} = \pi$$ **d)** For 225°: $$225 \times \frac{\pi}{180} = \frac{225\pi}{180} = \frac{5\pi}{4}$$ **e)** For 270°: $$270 \times \frac{\pi}{180} = \frac{270\pi}{180} = \frac{3\pi}{2}$$ \boxed{\text{Final answers for part 1: } a) \frac{\pi}{6}, b) \frac{\pi}{3}, c) \pi, d) \frac{5\pi}{4}, e) \frac{3\pi}{2}} 2. **Convert radians to degrees using the formula:** $$\text{Degrees} = \text{Radians} \times \frac{180}{\pi}$$ **a)** For 3 radians: $$3 \times \frac{180}{\pi} \approx 3 \times 57.2958 = 171.9^\circ$$ **b)** For 1.5 radians: $$1.5 \times \frac{180}{\pi} \approx 1.5 \times 57.2958 = 85.9^\circ$$ **c)** For 4.32 radians: $$4.32 \times \frac{180}{\pi} \approx 4.32 \times 57.2958 = 247.5^\circ$$ \boxed{\text{Final answers for part 2: } a) 171.9^\circ, b) 85.9^\circ, c) 247.5^\circ} 3. **Find the radius of a circle given circumference:** Formula: $$C = 2\pi r \Rightarrow r = \frac{C}{2\pi}$$ Given: $$C = 360 \text{ cm}$$ Calculate radius: $$r = \frac{360}{2\pi} = \frac{360}{6.283} \approx 57.3 \text{ cm}$$ \boxed{\text{Final answer for part 3: Radius } = 57.3 \text{ cm}}