Peri sued Denucci for a libelous letter received by Investigator. The authenticity and contents of the letter are disputed.Peri's attorney asks Investigator to testify that, a week before receiving the libelous letter, he had written to Denucci inquiring about Peri. The testimony is
admissible provided that this inquiry was made in the regular course of Investigator's business. admissible without production of the inquiry letter or the showing of its unavailability. inadmissible unless Peri's attorney has  given Denucci notice of Investigator's intended testimony. inadmissible unless the inquiry letter itself is shown to be unavailable.