Symptoms include: 1  Itching. 2  Significant tearing and production of thick mucus. 3  The feeling of having something in the eye (foreign body sensation) 4  Aversion to light (photophobia)
Geographic coordinate system. Longitude lines are perpendicular to and latitude lines are parallel to the equator. A geographic coordinate system is a coordinate system used in geography that enables every location on Earth to be specified by a set of numbers, letters or symbols. The coordinates are often chosen such that one of the numbers represents a vertical position, and two or three of the numbers represent a horizontal position.
Unlike latitude lines, longitude lines are not parallel. Meridians meet at the poles and are widest apart at the equator. Zero degrees longitude (0Â°) is called the prime meridian. The degrees of longitude run 180Â° east and 180Â° west from the prime meridian. geographic coordinates. Latitude and longitude lines form an imaginary grid over the Earth's surface.