A motorboat shall not be required to be numbered under the Boat Act if it is:

A. already covered by a number in force which has been awarded to it pursuant to federal law or a federally approved numbering system of another state; provided that the boat shall not have been within this state for a period in excess of ninety consecutive days;

B. a motorboat from a country other than the United States temporarily using the waters of this state;

C. a motorboat whose owner is the United States, a state or a subdivision thereof; D. a ship’s lifeboat; or

E. a motorboat belonging to a class of boats which has been exempted from numbering by the division after it has found that the numbering of motorboats of that class will not materially aid in their identification; and, if an agency of the federal government has a numbering system applicable to the class of motorboats to which the motorboat in question belongs, after the division has further found that the motorboat would also be exempt from numbering if it were subject to the federal law.