(a) It shall be unlawful for any person to operate a low-speed vehicle on any street or highway with a posted speed limit greater than 40 miles per hour.

(b) The provisions of subsection (a), shall not prohibit a low-speed vehicle from crossing a street or highway with a posted speed limit in excess of 40 miles per hour.

(c) This section shall be a part of and supplemental to the uniform act regulating traffic on highways.