41.   Biologists like to consider each run of salmon a different set of the species.

42.   Boeing faces a different set of challenges.

43.   A debate cast in terms of formative politics would focus on a different set of questions, a larger set of actors and a longer period of time.

44.   A company with a large market share that tries to merge with another major company in a similar market poses a different set of issues.

45.   A computerized cookbook clearly requires a different set of instincts.

46.   A different set of troubled souls haunt contemporary Japanese.

47.   A good tune can have a dozen different sets of words.

48.   A different set of blood vessels deep inside the dolphins was more baffling.

49.   A different set of personal problems compromised the play of fifth-seeded Lindsay Davenport.

50.   A separate case already pending before the justices challenges a different set of federal rules that restrict indecent programs on public-access cable television channels.