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.
Lines of Longitude define how far east or west a location is from the Prime Meridian, the focus of this lesson. The Prime Meridian is an imaginary line that, similar to the equator, divides the earth into eastern and western hemispheres. It is sometimes referred to as the Greenwich Meridian. All lines of latitude and longitude are measured in degrees.