What is the test for finding a defendant guilty beyond a reasonable doubt?

defendant guilty beyond a reasonable doubt.' [Citation] '[T]he relevant question is whether, after viewing the evidence in the light most favorable to the prosecution, any rational trier of fact could have found the essential elements of the crime beyond a reasonable doubt.' [Citations.] '[I]t is the jury, not the appellate court which must be convinced of the defendant's guilt beyond a reasonable doubt.' [Citation.]" (People v. Lewis (2009) 46 Cal.4th 1255, 1289-1290, fn. omitted.)

"Section 240 defines assault: 'An assault is an unlawful attempt, coupled with a present ability, to commit a violent injury on the person of another.'" (People v. Griggs (1989) 216 Cal.App.3d 734, 739.) "Although temporal and spatial considerations are relevant to a defendant's 'present ability' under section 240, it is the ability to inflict injury on the present occasion that is determinative, not whether injury will necessarily be the instantaneous result of the defendant's conduct." (People v. Chance (2008) 44 Cal.4th 1164, 1171.)