7-7-2: CLEAR VISION:
   A.   It is unlawful to operate any vehicle which is so loaded or in such a condition that the operator does not have a clear vision of all parts of the roadway essential to the safe operation of the vehicle.
   B.   Any vehicle with the view of the roadway to the rear so obstructed shall be equipped with a mirror so attached as to give him a view of the roadway behind him. (1977 Code § 10.44.010)