speed = distance covered divided by time spend travelling that distance. or s = d / t. If the distance is in miles and the time is in hours then the speed is given in miles per hour
http://wiki.answers.com/Q/What_is_the_simple_formu...

A popular model for yield curves is the threefactor DieboldLi model, where t represents today's date, represents the time to maturity of a particular bond, and L, S, C, and are
http://www.quora.com/Whataresomeformulasthatc...

n. A curve, such as a circle, that is closed and does not intersect itself. Also called Jordan curve .
http://www.answers.com/topic/curve1
