What is the test for determining the sufficiency of evidence in a criminal conspiracy case?

"In reviewing the sufficiency of the evidence, this court must determine 'whether a reasonable jury, after viewing the evidence in the light most favorable to the government, could have found the [defendant] guilty beyond a reasonable doubt of each essential element of the crime charged.' " United States v. Hernandez, 876 F.2d 774, 777 (9th Cir.1989) (quoting United States v. Douglass, 780 F.2d 1472, 1476 (9th Cir.1986)). In doing so, this court " 'must respect the exclusive province of the jury to determine the credibility of witnesses, resolve evidentiary conflicts, and draw reasonable inferences from proven facts, by assuming that the jury resolved all such matters in a manner which supports the verdict.' " United States v. Gillock, 886 F.2d 220, 222 (9th Cir.1989) (quoting United States v. Ramos, 558 F.2d 545, 546 (9th Cir.1977)).

1. Conspiracy

"The elements of conspiracy are 1) an agreement to accomplish an illegal objective, 2) coupled with one or more acts in furtherance of the illegal purpose, and 3) the requisite intent necessary to the underlying substantive offense." United States v. Penagos, 823 F.2d 346, 348 (9th Cir.1987).