Wholesale price increases in the United States slowed sharply last month as food and energy costs declined, a sign that inflationary pressures may be easing as the Federal Reserve considers whether to keep raising interest rates to fight higher prices. From January to February, the government’s producer price index fell 0.1%, after a 0.3% rise from December to January. Compared with a year ago, wholesale prices rose 4.6%, a big drop from the 5.7% annual increase in January.