Definition: This tells the distance east or west of the Prime Meridian.

Term:

Explanation:

Longitude measures the number of degrees EAST or WEST of the Prime Meridian which runs through Greenwich, England. The Prime Meridian has a longitude of 0 . Lines of longitude (meridians) running north-south around the globe measure distances EAST and WEST of the Prime Meridian.

could you go a bit more in depth with you question? it's quite hard to understand. as soon as you do that i will be glad to : )

answer; unimodal and symmetrical;