al, 425 U.S. 738, 96 S. Ct. 1848, 48 L. Ed. 2d 338 (1976); Gulf Oil Corp. v. Copp Paving Co., 419 U.S. 186, 95 S. Ct. 392, 42 L. Ed. 2d 378 (1974); Burke v. Ford, 389 U.S. 320, 88 S. Ct. 443, 19 L. Ed. 2d 554 (1967). If so, [HN6] even a wholly intrastate activity may be regulated by the Sherman Act where that