(a) Service of interrogatories. Any party may serve upon any other party written interrogatories, not to exceed 25 in number, including all discrete subparts, unless additional interrogatories are agreed to by the parties or leave to serve additional interrogatories is granted by the hearing officer.

(b) Response to interrogatories. Within 20 days after service of the request, the party upon whom the interrogatories are served shall serve a written response, unless the parties agree in a written document submitted to the hearing officer or the hearing officer determines that a shorter or longer period is appropriate under the circumstances. The response shall specifically answer each interrogatory, separately and fully in writing, unless it is objected to, in which event the objecting party shall state the reasons for any objections with specificity. Any ground not stated in a timely objection is waived unless the party's failure to object is excused by the hearing officer for good cause shown. If objection is made to only part of an interrogatory, the objectionable part shall be specified and the party shall answer to the extent that the interrogatory is not objectionable.

(c) Option to produce business records. Where the answer to an interrogatory may be derived or ascertained from the business records, including electronically stored information, of the party upon whom the interrogatory has been served or from an examination, audit, or inspection of such business records, including a compilation, abstract, or summary thereof, and the burden of deriving or ascertaining the answer is substantially the same for the party serving the interrogatory as for the party served, it is a sufficient answer to such interrogatory to specify the records from which the answer may be derived or ascertained and to afford to the party serving the interrogatory reasonable opportunity to examine, audit, or inspect such records and to make copies, compilations, abstracts, or summaries. A specification shall be in sufficient detail to permit the interrogating party to locate and to identify, as readily as can by the party served, the records from which the answer may be ascertained.