DART <DARTA> MAKES OFFER FOR SUPERMARKETS <SGL> Dart Group Corp said it offered to buy Supermarkets General Corp for 41.75 dlrs per share in cash. Earlier Supermarkets General said an "unsolicited third party" had made the offer. Analysts estimated the value at about 1.6 billion dlrs, based on 38.5 mln shares outstanding. Kidder, Peabody and Co Inc told Dart that Kidder's affiliate will be prepared to advance up to 750 mln dlrs on a subordinated basis.