



 
Hi Samua, The distance from one city to another is an arc length since Earth is approximately a sphere. Derived from the circumference formula and the fact that a circle has 360^{o}, we get the following arc length formula for degrees: s = (θπr)/180 where θ is the angle between the cities, r is the radius of the Earth and s is the distance between the cities. To find the angle between the cities you will have to subtract their latitudes since both is a measure from the equator and not form each other. Hope this helps, Janice
 


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