Whether a leadership enhancement under U.S. Sentencing Guidelines 3B1.1(a) is permissible when drug quantity is extrapolated without chemist testimony and involves uncharged participants

■ WHEN FEDERAL defendants are ' BASED ON EXTRAPOLATION AND AS TO HOW THE EXTRAPOLATION EVIDENCE IN THE RECORD DOESATTRIBUTED A DRUG QUANTITY THE CHEMIST FAILS TO TESTIFYWAS CONDUCTED AND THERES NO THIS REQUIRE REVERSAL WHEN DEFENDANTS RECEIVE AN LEADERSHIP ENHANCEMENT UNDER 3B1.1(A) WHICH INVOLVED 5 OR MORE PARTICIPANTS NOT CHARGED IN THE INSTANT INDICTMENT BUT ARE INDICTMENT IS THE ENHANCEMENT PERMISSIBLEBUT THE 5 PARTICIPANTS ARE CHARGED IN A SEPARATE