7. The period for which a person shall be appointed to fill a seat shall be—
(i) in the case of a person appointed to fill a seat in the Council of State—
(a) by the Ruler of a State entitled to separate representation, nine years;
(b) jointly by the Rulers of all the States in a group which have acceded to the Federation, three years;
(c) by the Ruler of a State appointing in rotation, one year subject, however, to the special provisions of the next succeeding paragraph with respect to certain States therein mentioned;
(d) jointly by Rulers of some only of the States in a group which have acceded to the Federation, a period equal to the aggregate of the periods for which each of them might in rotation have appointed a person to hold that seat or three years, whichever may be the shorter period;
(e) in any other manner, three years; and
(ii) in the case of a person appointed to fill a seat in the Federal Assembly, until the dissolution of the Assembly :
Provided that—
(i) a person appointed to fill a seat upon the occurrence of a casual vacancy shall be appointed to fill that seat for the remainder of the period for which his predecessor was appointed;
(ii) in the case of first appointments to fill seats in the Council of State the Governor-General in his discretion shall make by order provision for securing that approximately one-third of the persons appointed by Rulers entitled to separate representation shall be appointed to fill seats for three years only, approximately one-third to fill seats for six years only and approximately one-third to fill seats for nine years.