1. Know how to read and find locations given a degree of longitude and latitude.

Longitude: the angular distance of a place east or west of the meridian at Greenwich, England, or west of the standard meridian of a celestial object. This is usually expressed in degrees or minutes.

Latitude: A coordinate that specifies the north–south position of a point on the Earth's surface. Latitude is an angle which ranges from 0° at the Equator to 90° at the poles. Lines of constant latitude, or parallels, run east–west as circles parallel to the equator.

Cause of he different elevations  hope this ?