Question

Assuming that Earth is a sphere of radius 6378 kilometers, what is the difference in the latitudes of Syracuse, New York and Annapolis, Maryland, where Syracuse is about 450 kilometers due north of Annapolis?

Answer 1

For the answer to the question above asking, what is the difference in the latitudes of Syracuse, New York and Annapolis, Maryland, where Syracuse is about 450 kilometers due north of Annapolis?
Draw a circle.
On the right half of the circle put two different dots. The upper dot is Syracuse and the lower is Annapolis.
Label the arc between them 450km.

Draw the radii to the dots and label them 6378km.
Determine the central angle θ:
θ = arclength×180/(πr)
= 450×180/(π6378)
= 4°
or
4.0425° to be exact. I hope this helps