(d) To appoint all county officers whose election by the electors is not required by the constitution, except county supervisors and the county auditor or comptroller, and for such terms of office as are provided by law.
Subject to resolutions of the board of supervisors he shall
(e) Purchase all supplies and materials required by every county officer, including the superintendents of the poor;
(f) Execute contracts on behalf of the board of supervisors when the consideration therein shall not exceed five hundred dollars;
(g) Obtain from the several county officers reports of their various activities, in such form and at such times as the board of supervisors may require;
(h) Obtain from the several county officers itemized estimates of the probable expense of conducting their offices for the ensuing year, and transmit the same to the board of supervisors with his approval or disapproval of each and all items therein, in the form of a tentative budget;
(i) Perform such other duties as the board of supervisors may require.
In the exercise of the foregoing duties, the county manager shall have the same powers to examine witnesses, to take testimony under oath and to investigate the affairs of every county officer which is conferred by this chapter upon the boards of supervisors and committees thereof.
§ 248. The administrative code. Within ninety days after the first day of operation under this article, the board of supervisors shall adopt, publish in pamphlet form and cause to be delivered to every officer of the county, and to such other persons as shall apply for the same, a code of administrative rules. Such code, subject to such regulations concerning the conduct of various county officers as may be made from time to time by the comptroller, shall contain the rules of the said board on the following subjects:
(a) The methods by which the county manager shall exercise the duties imposed upon him in sub-divisions (e) to (i), inclusive, of section two hundred and forty-seven of this article.