NEC Corp., a leading Japanese electronics maker,...

NEC Corp., a leading Japanese electronics maker, will set up an institute in Princeton, N.J., to do basic computer and communications research . . . West Point Pepperell Inc. said it completed the acquisition of all of the outstanding common stock of J.P. Stevens & Co. through a merger of a wholly owned subsidiary of West Point into Stevens . . . Monthly mutual fund sales fell to $7.1 billion in May from $9 billion in April and $13.5 billion in May 1987, the Investment Company Institute said . . . New World Entertainment Ltd. extended its currently ongoing exchange offers, previously scheduled to expire at 5 p.m. EDT Thursday, until 5 p.m. EDT, July 11 . . . The catalogue company L. L. Bean will locate a $50-million, state-of-the-art distribution center in Bangor, Me., that is scheduled to open in 1992 . . . The Navy awarded a $2.9-billion contract for the construction of two nuclear-powered Nimitz class aircraft carriers to Newport News Shipbuilding and Dry Dock Co. of Newport News, Va. The carriers are to be completed before June, 1998.