United States v. McDonald, 61 F.3d 248, 255 (4th Cir.1995) (providing review standard for quantity of drugs attributable to a defendant for sentencing). The record reveals Freshour’s extensive manufacturing and distributing of the drug over an extended period of time, which supports the court’s factual findings on the matter. Second, the district court’s calculation of Freshour’s advisory sentencing range and imposition of a sentence within the statutory maximum does not offend the Sixth Amendment, as he was sentenced below the statutory maximum for the offense with no drug weight. See 21 U.S.C.A. § 841(b)(1)(C) (West Supp.2009) (twenty-year maximum punishment for an unspecified amount of methamphetamine); Rita v. United States, 551 U.S. 338, 347, 127 S.Ct. 2456, 168 L.Ed.2d 203 (2007) (<HOLDING>); United States v. Booker, 543 U.S. 220,
holding that a court of appeals may afford a presumption of reasonableness to a withinguidelines sentence holding that we may apply a presumption of reasonableness to a sentence within the guidelines range holding that a court of appeals may presume reasonable a district courts proper application of the sentencing guidelines holding that a court of appeals may apply a presumption of reasonableness to a district court sentence that reflects a proper application of the sentencing guidelines holding that district court may not presume reasonableness of guidelines sentencing range in particular case