Profit at Boston Beer Co. fell in the first quarter as rising costs and intense competition dampened sales gains for the maker of Samuel Adams beer, Twisted Tea, and other beverages. The company said in addition to facing higher costs, it increased spending on advertising and promotions. Those expenses, however, were partially offset by a favorable tax settlement. Boston Beer reported net income of $6.9 million, or 51 cents per share, down from $7.5 million, or 56 cents, a year before. Revenue rose 20 percent to $135.9 million.