What is the test for notice and demand in a personal injury case?

The date on which a given event occurs is clearly a matter of fact. Factual questions are ordinarily determined by the trier of fact, in this case the jury. The rule is no different in tax collection and refund suits. See United States v. Fred A. Arnold, Inc., 573 F.2d 605, 606 (9th Cir.1978). We thus conclude that the district court erred in treating the question of notice and demand as a matter to be decided by the court. ⁸