There shall be exempted from the provisions of this chapter:
(1) Motor vehicles while engaged exclusively in the delivery of United States mail;
(2) Motor vehicles owned and operated by the government of the United States;
(3) Motor vehicles owned and operated by a cooperative group and used exclusively for the transportation of the property of the cooperative group or its members;
(4) Motor vehicles used exclusively in the transportation of agricultural commodities or horticultural commodities or products from a farm, or farm supplies to a farm;
(5) Motor vehicles engaged in the plowing or removal of snow from the publicly used highways within this state;
(6) Motor vehicles engaged in the transportation of garbage, ashes, and debris removed from private dwellings, commercial, and industrial establishments;
(7) Motor vehicles engaged exclusively in transporting newspapers.