“Districts” consist of the following:
(a) District 1 consists of the California Counties of El Dorado, Marin, Napa, Sacramento, Solano, Sonoma, and all counties north of these counties.
(b) District 2 consists of the California Counties of Inyo, Kern, San Luis Obispo, and all counties north of these counties up to the southern boundary of District 1.
(c) District 3 consists of the California counties south of District 2.
(d) District 4 consists of all areas not in California.