[UNPUBLISHED] PER CURIAM. Ashley Springer appeals the 60-month prison sentence imposed by the district court after she pleaded guilty to conspiracy to manufacture and distribute crack cocaine and to distribute powder cocaine in violation of 21 U.S.C. § 846, and distribution of crack cocaine in violation of 21 U.S.C. § 841(a)(1), (b)(1)(
B) and 18 U.S.C. § 2. Acknowledging that this sentence was the statutory minimum, Springer argues that application of the 100 to 1 ratio for quantities of powder cocaine and crack cocaine results in an improper disparity between the Guideline ranges for the two drugs, and she requests resentencing using the lower range produced by a 20 to 1 ratio. Springer’s argument is foreclosed by United States v. Spears, 469 F.3d 1166, 1176 (8th Cir.2006) (en banc), which held that neither United States v. Booker, 543 U.S. 220, 125 S.Ct. 738, 160 L.Ed.2d 621 (2005), nor 18 U.S.C. § 3553(
a) authorizes district courts to reject the 100 to 1 ratio mandated by Congress and reflected in the Guidelines. We conclude that the sentence is not unreasonable. See Booker, 543 U.S. at 261-62, 125 S.Ct. 738 (standard of review); United States v. Pamperin, 456 F.3d 822, 824 (8th Cir.2006) (district court, without 18 U.S.C. § 3553(
e) motion by government, was without authority to impose sentence below statutory minimum). Accordingly, we affirm. . The Honorable Mark W. Bennett, United States District Judge for the Northern District of Iowa.