The motion for leave to file brief of National Congress of Petroleum Retailers, Inc., and Retail Gaso*951line Dealers Association of Michigan, Inc., as amici curiae, is granted. Petition for writ of certiorari to the United States Court of Appeals for the Seventh Circuit granted.
Solicitor General Rankin, Assistant Attorney General Hansen, Earl W. Kintner and Robert B. Dawkins for petitioner. Weymouth Kirkland, Howard Ellis, Hammond E. Chaffetz, W. H. Van Oosterhout and Thomas E. Sunderland for respondent. Cyrus Austin for the National Congress of Petroleum Retailers, Inc., et al.