Convictions and sentences for multiple counts relating to an armored car robbery in which a security guard was killed, are affirmed over claims that: 1) the government failed to demonstrate co-defendant's involvement in the conspiracy to commit robbery or in the carrying and use of a firearm in furtherance of that conspiracy; 2) the government failed to prove that co-defendant had the requisite malice aforethought in the commission of the murder; 3) the district court erred in admitting witness testimony regarding the March 6, 2002 attempted robbery; and 4) the district court erred in denying co-defendant's request for a downward adjustment for a minor role.