What is the test for determining whether the prosecution sustained its burden of proving the elements of a sentence enhancement beyond a reasonable doubt?

"On review, we examine the record in the light most favorable to the judgment to ascertain whether it is supported by substantial evidence. In other words, we determine whether a rational trier of fact could have found that the prosecution sustained its burden of proving the elements of the sentence enhancement beyond a reasonable doubt. [Citations.]" (People v. Delgado (2008) 43 Cal.4th 1059, 1066-1067.)