(a) The board of trustees shall elect a chairman from its membership and shall employ a director who shall not be a trustee.

(b) The board of trustees shall engage such actuarial and other services as shall be required to transact the business of the retirement system.

(c) The director and all other employees of the board of trustees shall be governed by such rules of position, classification, appointment, promotion, demotion, dismissal, transfer, qualification, compensation, seniority, privileges, tenure, and other employment standards as may now or hereafter be established under the State Merit System of Personnel Administration.

(d) The board of trustees shall pay its pro rata share of the administrative costs of operating the State Merit System of Personnel Administration in the manner prescribed in paragraph (6) of subsection (b) of Code Section 45-20-4.