Short-term Treasury yields, the most sensitive to monetary policy changes, fell on Friday after the Justice Department dropped its investigation into the central bank, potentially opening a path for President Donald Trump’s pick, Kevin Warsh, to become Fed chair and push for interest-rate cuts. Yields on Treasuries have been confined to narrow ranges with expectations for a Fed rate cut by the end of the year swinging between a roughly 25% to 60% chance over the past week or so.