What is the test for reasonable detention under the Fourth Amendment?

applicable law applies to the facts is a mixed question of law and fact that is subject to independent review. [Citation.]" (People v. Ramos (2004) 34 Cal.4th 494, 505.)

"A detention is reasonable under the Fourth Amendment when the detaining officer can point to specific articulable facts that, considered in light of the totality of the circumstances, provide some objective manifestation that the person detained may be involved in criminal activity." (People v. Souza (1994) 9 Cal.4th 224, 231 (Souza).)