The board of supervisors may provide that the fourth and fifth members, and in counties having a board consisting of nine members or nine members and an alternate retired member, the fourth, fifth, sixth, eighth, ninth, and alternate retired members, and in counties having a board of investments under Section 31520.2, the fifth, sixth, seventh, eighth, and ninth members of the board of investments, shall receive compensation at a rate of not more than one hundred dollars ($100) for a meeting, or for a meeting of a committee authorized by the board, for not more

than five meetings per month, together with actual and necessary expenses for all members of the board.