Question

Assume that the Earth is spherical and recall that latitudes range from 0° at the Equator to 90° N at the North Pole. Consider Dubuque, Iowa (42.50° N latitude), and Guatemala City (14.62° N latitude). The two cities lie on approximately the same longitude. Do not neglect the curvature of the Earth in determining the following.

If one could burrow through the Earth and dig a straight-line tunnel from Dubuque to Guatemala City, how long would the tunnel be?

i know the answer for this part and its 3072992.8 m...i need help with the next part

From the point of view of the digger, at what angle below the horizontal would the tunnel be directed?

Answer 1

I thought I answered this already.

sin^-1[L/(2R)] is the answer

Answer 2

http://www.jiskha.com/display.cgi?id=1329345775