A multi-platinum-selling singer is the latest star to fire long-time Hollywood manager Benny Medina. Mariah Carey has let go of the high-profile handler, whose name is widely known in the realms of TV and music. Talk show host and “America’s Top Model” star Tyra Banks also dropped Medina, who helped produce her TV productions. Singer Usher let the veteran manager go, as well, in the midst of his on-and-off representation by his mom.