1. **State the problem:** We are given two points on the Earth: A(50°, 32W) and B(50°, 32E). We need to find the distance between these points, given the Earth's radius $R=6400$ km and take $\pi = 3.14$. 2. **Understand the coordinates:** Both points have the same latitude $50^\circ$, but their longitudes are $32^\circ$ west and east respectively. Since they lie on the same latitude, the shortest path along the surface is along the circle of latitude. 3. **Calculate the central angle between the points:** The longitude difference is $32^\circ + 32^\circ = 64^\circ$. This is the angle at the Earth's center between the two points along the circle of latitude. 4. **Calculate the radius of the circle of latitude:** The radius at latitude $\theta$ is $R \cos \theta$. Here, $\theta = 50^\circ$. $$r = 6400 \times \cos 50^\circ$$ Calculate $\cos 50^\circ$: $\cos 50^\circ \approx 0.6428$ So, $$r = 6400 \times 0.6428 = 4113.92 \text{ km}$$ 5. **Calculate the arc length between points:** The arc length $s = r \times \text{angle in radians}$. Convert $64^\circ$ to radians: $$64^\circ = 64 \times \frac{\pi}{180} = 64 \times \frac{3.14}{180} = 1.113 \text{ radians}$$ Now compute the arc length: $$s = 4113.92 \times 1.113 = 4578.8 \text{ km}$$ 6. **Final Answer:** The distance between points A and B along the Earth's surface at latitude $50^\circ$ is approximately **4579 km**.