ARCGIS TRAINING questions with correct answers

What is the difference between a Projected Coordinate System and a Geographic Coordinate System? Answer A Geographic Coordinate System is used to locate objects on the curved surface of the Earth. A Projected Coordinate System is used to locate objects on a flat surface, e.g. a paper map [What are the features of a Geographic Coordinate System? How do they measure/indicate location?] Answer Graticule - consists of intersecting vertical and horizontal lines, which are called longitude (meridians) and latitude (parallels) respectively. Measurements are expressed in degrees, minutes, and seconds. What is an attribute? Answer Information about a geographic feature in a GIS, generally stored in a table and linked to the feature by a unique identifier. For example, attributes of a river might include its name, length, and average depth. What is a class? Answer A group or category of attribute values; a set of entities possessing certain common attribute values. What is a coordinate system? Answer A reference system used to locate geographic features on a two- or three-dimensional surface. A coordinate system is comprised of a spheroid, datum, projection, and units. Common coordinate systems are geographic (three-dimensional), in which locations are measured in degrees of latitude and longitude, and planar (also called projected or Cartesian), in which the earth's surface is projected