977a7327_Si_units____Anthology_of_Ideas__Notes
[Name] Length [Abbreviation (Symbol)] l, x (for distances) [Standard Unit] Meter (m) [Notes] 
A meter is defined as the distance light travels in a vacumm in of a second (in physics it is customary to use metric measurements although the basic principles apply if you to use feet instead of meters)
Units in Physics (mechanical, electricity, magnetism, light and optics) including Si units. | Anthology of Ideas
Notes