(a) Any party may serve, by mail or delivery by hand, upon any other party written interrogatories relating to any matters which may be inquired into under Rule 21.
(b) A party may propound more than one set of interrogatories to an adverse party, but the total number of interrogatories shall not exceed 25, unless the court otherwise orders for good cause shown after the proposed additional interrogatories have been filed with the court. In determining what constitutes an interrogatory for the purpose of applying this limitation in number, it is intended that each question be counted separately, whether or not it is subsidiary or incidental to or dependent upon or included in another question, and however the questions may be grouped, combined or arranged.
(c) Any party p