591 F.3d 780, 784 (5th Cir.2009). 14 . United States v. Templeton, 624 F.3d 215, 221 (5th Cir.2010), cert. denied,-U.S.-, 131 S.Ct. 1530, 179 L.Ed.2d 346 (2011). 15 . Fed.R.Evid. 404(b). 16 . Id. 17 . Templeton, 624 F.3d at 221 (citing United States v. Beechum, 582 F.2d 898, 911 (5th Cir.1978) (en banc)). 18 . Id. (citing Beechum, 582 F.2d at 911). 19 . Id. (citing United States v. Cockrell, 587 F.3d 674, 678 (5th Cir.2009)); see Fed.R.Evid. 403. 20 . United States v. Hernandez-Guevara, 162 F.3d 863, 872 (5th Cir.1998). 10 . See Olano, 507 U.S. at 734, 113 S.Ct. 1770. 11 .See id. ("In most cases, a court of appeals cannot correct the forfeited error unless the defendant shows that the error was prejudicial.”). 21 . See United States v. Lindell, 881 F.2d 1313, 1319 (5th Cir. 1989) (<HOLDING>). 22 . See United States v. Leahy, 82 F.3d 624,
holding that the evidence did not plausibly support a buyerseller instruction because overwhelming evidence showed that defendants agreed to import drugs with the intent to distribute them and engaged in repeated transactions of large quantities of narcotic drugs for resale recognizing that even evidence of a defendants and a witnesss prior bad acts was admissible to show inter alia the defendants familiarity with the witness holding that trial court could properly determine that evidence of a gun was relevant to the charge of possession with intent to sell or deliver cocaine because as a practical matter firearms are frequently involved for protection in the illegal drug trade holding that evidence of the defendants personal cocaine use was relevant to their knowledge regarding the charge of conspiring to import marijuana because it demonstrated their familiarity with illegal drugs holding that it was proper for court to rely on affidavits of defendants representatives in negotiations because their personal knowledge and competence to testify are reasonably inferred from their positions and the nature of their participation in the matters to which they swore