What is the prosecution's burden to prove every element of a crime beyond a reasonable doubt?

"It is the prosecution's burden in a criminal case to prove every element of a crime beyond a reasonable doubt." (People v. Cuevas (1995) 12 Cal.4th 252, 260, citing In re Winship (1970) 397 U.S. 358.) "To determine whether the prosecution has introduced sufficient evidence to meet this burden, courts apply the `substantial evidence' test. Under this standard, the court `must review the whole record in the light most favorable to the judgment below to determine whether it discloses substantial evidencethat is, evidence which is reasonable, credible, and of solid valuesuch that a reasonable trier of fact could find the defendant guilty beyond a reasonable doubt.' " (Cuevas, at p. 260, quoting People v. Johnson (1980) 26 Cal.3d 557, 578.)

The mental state necessary to convict a defendant as an aider and abettor is different from the mental state necessary to convict an actual perpetrator. (People v. Mendoza (1998) 18 Cal.4th 1114, 1122.) "The actual perpetrator must have whatever mental state is required for each crime charged . . . . An aider and abettor, on the other hand, must `act with knowledge of the criminal purpose of the perpetrator and with an intent or purpose either of committing, or of encouraging or facilitating commission of, the offense.' [Citation.]" (Id. at p. 1123.)