(1) Of the Senators-

a) one-third or their number (excluding any Senator who holds the office of Attorney-General) shall be appointed by the Governor-General, acting in accordance with the advice of the Leader to the Opposition; and

b) the others shall be appointed by the Governor-General, acting in accordance with the advice of the Prime Minister.

(2) In this section "one-third" means, in relation to a number of Senators that is not a multiple of three, one-third of the next higher number that is such a multiple.