American historian Richard Breitman published a new study in Washington yesterday, proving that the American administration under President Franklin Roosevelt knew as early as the spring of 1942 about the German plan to wipe out all of European Jewry. The study is based on 400,000 pages of National Archives documentation whose \"secret\" classification was removed last year. Among the papers Breitman found a telegram sent by a Chilean diplomat from Berlin to Santiago enumerating details of the Nazis\' \"Final Solution.\"