By consent and approval of a majority of any committee, the chairman may designate a subcommittee of not less than five persons to conduct hearings, call witnesses, and inquire into any matters properly before the committee. A duly constituted subcommittee shall have all of the powers of the full committee, but any subcommittee shall cease its activities upon majority vote of the full committee, or as provided in N.C. Gen. Stat. § 120-19.6 (1973, c. 543.)