ALSO. . .

West Covina-based California State Bank posted fourth-quarter profit of $2.7 million, or 49 cents per share (diluted), compared with $2 million, or 37 cents per share (diluted), for the same period in 1996. . . . Cabletron Systems Inc. agreed to buy the 76% of Sunnyvale-based Yago Systems it doesn’t already own for about $87.8 million in stock to acquire equipment that connects computer networks at high speeds. . . . Bay Networks Inc. said it will purchase closely held New Oak Communications for $156 million in cash and stock to broaden its Internet-based product lines.