R.I. Gen. Laws § 45-50-7: Officers and quorums.

The authority shall elect one of its members as chairperson and another as vice chairperson and shall also elect a secretary and a treasurer. Three (3) members of the authority constitutes a quorum and the vote of three (3) members is necessary for any action taken by the authority. No vacancy in the membership of the authority shall impair the right of a quorum to exercise all the rights and perform all the duties of the authority; provided, however, that the provisions of this section shall not apply to an authority authorized pursuant to § 45-50-3(c), in which case the public law providing for the exercise of the powers of the authority by a body corporate and politic shall apply and be considered definitive.