By Howard Schneider and Ann Saphir WASHINGTON (Reuters) – The Federal Reserve raised its benchmark overnight interest rate by three-quarters of a percentage point on Wednesday in an effort to cool the most intense breakout of inflation since the 1980s, with “ongoing increases” in borrowing costs still ahead despite evidence of a slowing economy. “Inflation remains elevated, reflecting supply and demand imbalances related to the pandemic, higher food and energy prices, and broader price pressures,” the rate-setting Federal Open Market Committee said as it lifted the policy rate to a range of be…