There are . Federal Reserve regional banks. The Federal Reserve's role as a lender of last resort involves lending to which of the following financially troubled institutions? O U.S. banks that cannot borrow elsewhere the discount rate O Governments in developing countries during currency crises the reserve requirement O U.S. state governments when they run short on tax revenue open market operations The Federal Reserve's primary tool for changing the money supply is . In order to increase the number of dollars in the U.S. economy (the money supply), the Federal Reserve will government bonds