General Motors said it had placed 1,500 hourly workers on indefinite layoff at various plants in its U.S. manufacturing system due to production adjustments at various GM divisions . . . Dallas-based Zale Corp. said it will not comment on the Peoples Jewellers bid, but that it will study the proposal "with a view to responding in November" . . . Sunrise Medical Center in Torrance said its board of directors approved a definitive agreement to acquire Motion Designs Inc., a Fresno-based wheelchair manufacturer, for undisclosed terms . . . The Investment Company Institute reported that the assets of the nation's 375 money-market mutual funds fell $934.5 million in the week ended Oct. 29.