BY BLOOMBERG Treasuries fell after the U.S. auctioned $13 billion of 30-year bonds amid signs the world's biggest economy is gathering strength. Losses were tempered as yields at almost 11-month highs attracted buyers. The sale drew a yield of 3.248%, the highest since March 2012, compared with an average forecast of 3.243% in a Bloomberg News poll of seven of the Federal Reserve's 21 primary dealers. The bid-to-cover ratio, which gauges demand by