Plaintiff sued Defendant for injuries suffered in a car accident allegedly caused by brakes that had been negligently repaired by Defendant. At a settlement conference, Plaintiff exhibited the brake shoe that caused the accident and pointed out the alleged defect to an expert, whom Defendant had brought to the conference. No settlement was reached. At trial, the brake shoe having disappeared, Plaintiff seeks to testify concerning the condition of the shoe. Plaintiff's testimony is 
admissible, because Defendant's expert had been able to examine the shoe carefully.  admissible, because Plaintiff had personal knowledge of the shoe's condition.  inadmissible, because the brake shoe was produced and examined as a part of settlement negotiations.  inadmissible, unless Plaintiff establishes that the disappearance was not his fault.