by Belinda h. December 07, 2003
by jako July 27, 2003
by Denozzo August 03, 2008
by Philip Stephenson November 30, 2004
by Hareeln August 13, 2012
The length of the path travelled by light in a vacuum during a time interval of 1/299,792,458 of a second
by America Lover 🇺🇸 November 17, 2018