Surveying FS

Answer: A - The National Geodetic Survey defines the geoid as “the equipotential surface of the Earth’s gravity field which best fits, in a least squares sense, global sea level.” The geoid is a 3-dimensional surface that fits as closely as possible to gravity measurements taken at locations throughout the world. Because the gravitational pull varies in response to differences in topography and the density of materials in the Earth’s interior, the geoid appears lumpy and squished at the equator.