WASHINGTON — U.S. inflation slowed last month and a measure of underlying price pressures also cooled, suggesting higher oil and gas prices from the Iran war are only having a limited impact on broader costs in the economy. Still, oil prices remain elevated and gas prices rose in late July and August, suggesting overall inflation could accelerate next month. Long-term interest rates rose after Warsh's comments, suggesting investors worried that inflation could worsen in the coming months and the Fed might not lift borrowing costs to fight rising prices.