(a) ascertain what constitutes the best tests for determining whether life is extinct, and shall prescribe the application of such tests, as he may deem necessary;
(b) investigate all alleged violations of law and of all rules and regulations relating to funeral directing, undertaking, and embalming;
(c) appoint such personnel as he may deem necessary, who, subject to the supervision, direction, and control of the commissioner, shall exercise the powers and perform the duties of the department and advise the commissioner under this article.