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the surface features of a place or region. The topography of a region includes hills, valleys, streams, lakes, bridges, tunnels, and roads
a two-dimensional, or flat, representation of Earth's surface or a portion of it as seen from above
an imaginary circle around the middle of the earth, halfway between the North Pole and the South Pole
line of the global grid running from the North Pole to the South Pole through Greenwich, England
Global Positioning System
a navigational system involving satellites and computers that can determine the latitude and longitude of a receiver on Earth by computing the time difference for signals from different satellites to reach the receiver
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