In the U.S. territory the speed limit is 20 mph in the city and 30 out in the country . U.S. states face patchwork of speed limits across the nation . Parts of Texas have speed limits of 100 miles per hour . Some researchers skeptical of link between low , high speed .
U.S. states face patchwork of speed limits across the nation . Parts of Texas have speed limits of 100 miles per hour . Some researchers skeptical of link between low , high speed .