What nationality was the man who determined that light has a finite speed?
Rømer's determination of the speed of light: Rømer's determination of the speed of light was the demonstration in 1676 that light has a finite speed, and so does not travel instantaneously. Rømer's determination of the speed of light:  The discovery is usually attributed to Danish astronomer Ole Rømer (1644–1710), who was working at the Royal Observatory in Paris at the time.
i don't know