<prompt> Ngwala tšwetšopele ya serapa se - Ka morago o ile a hudugela United States, moo a ilego a tsenela Yunibesithi ya Michigan kua Ann Arbor ka tlase ga tlhahlo ya mohlahli Jon Urbanchek, gotee le boramabelo ba go swana le Eric Namesnik, Gustavo Borges le Tom Dolan. Dipapading tša Dipapadi tša Meetse tša Ditšhabatšhaba tša 1993  <response>: kua Sheffield o thopile sefoka sa bronze ka lebelo la motho ka noši la 400 m. 