American Broadcasting Cos. agreed to sell a...

American Broadcasting Cos. agreed to sell a radio station in Detroit to Silver Star Communications for $14 million, and Capital Cities Communications reached a deal to sell two radio stations in Patterson, N.J., to Park Communications for an undisclosed sum. Both sales are related to the planned merger of ABC and Capital Cities . . . Baxter Travenol Laboratories agreed to sell its cardiopulmonary product line to Minnesota Mining & Manufacturing as part of Baxter’s plan to gain Justice Department approval of its merger with American Hospital Supply . . . Northern Telecom signed a $300-million supply contract with Nynex Material Enterprises . . . RCA and Bertelsmann of West Germany completed the merger of their worldwide record music publishing and music-video businesses . . . Continental Telecom will acquire Fairchild Industries’ interests in American Satellite Co. and Space Communications Co. for $105 million. Currently, the firms are equal partners in the two ventures.